| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pntrval.r | ⊢ 𝑅  =  ( 𝑎  ∈  ℝ+  ↦  ( ( ψ ‘ 𝑎 )  −  𝑎 ) ) | 
						
							| 2 | 1 | pntrsumbnd | ⊢ ∃ 𝑏  ∈  ℝ+ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 | 
						
							| 3 |  | 2rp | ⊢ 2  ∈  ℝ+ | 
						
							| 4 |  | rpmulcl | ⊢ ( ( 2  ∈  ℝ+  ∧  𝑏  ∈  ℝ+ )  →  ( 2  ·  𝑏 )  ∈  ℝ+ ) | 
						
							| 5 | 3 4 | mpan | ⊢ ( 𝑏  ∈  ℝ+  →  ( 2  ·  𝑏 )  ∈  ℝ+ ) | 
						
							| 6 |  | oveq2 | ⊢ ( 𝑚  =  ( 𝑘  −  1 )  →  ( 1 ... 𝑚 )  =  ( 1 ... ( 𝑘  −  1 ) ) ) | 
						
							| 7 | 6 | sumeq1d | ⊢ ( 𝑚  =  ( 𝑘  −  1 )  →  Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  =  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) | 
						
							| 8 | 7 | fveq2d | ⊢ ( 𝑚  =  ( 𝑘  −  1 )  →  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  =  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) ) | 
						
							| 9 | 8 | breq1d | ⊢ ( 𝑚  =  ( 𝑘  −  1 )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ↔  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 ) ) | 
						
							| 10 |  | simplr | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 ) | 
						
							| 11 |  | nnz | ⊢ ( 𝑘  ∈  ℕ  →  𝑘  ∈  ℤ ) | 
						
							| 12 | 11 | adantl | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  𝑘  ∈  ℤ ) | 
						
							| 13 |  | peano2zm | ⊢ ( 𝑘  ∈  ℤ  →  ( 𝑘  −  1 )  ∈  ℤ ) | 
						
							| 14 | 12 13 | syl | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  ( 𝑘  −  1 )  ∈  ℤ ) | 
						
							| 15 | 9 10 14 | rspcdva | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 ) | 
						
							| 16 | 5 | ad2antrr | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( 2  ·  𝑏 )  ∈  ℝ+ ) | 
						
							| 17 | 16 | rpge0d | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  0  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 18 |  | sumeq1 | ⊢ ( ( 𝑘 ... 𝑚 )  =  ∅  →  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  =  Σ 𝑛  ∈  ∅ ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) | 
						
							| 19 |  | sum0 | ⊢ Σ 𝑛  ∈  ∅ ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  =  0 | 
						
							| 20 | 18 19 | eqtrdi | ⊢ ( ( 𝑘 ... 𝑚 )  =  ∅  →  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  =  0 ) | 
						
							| 21 | 20 | abs00bd | ⊢ ( ( 𝑘 ... 𝑚 )  =  ∅  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  =  0 ) | 
						
							| 22 | 21 | breq1d | ⊢ ( ( 𝑘 ... 𝑚 )  =  ∅  →  ( ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 )  ↔  0  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 23 | 17 22 | syl5ibrcom | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( ( 𝑘 ... 𝑚 )  =  ∅  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 24 | 23 | imp | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  ( 𝑘 ... 𝑚 )  =  ∅ )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 25 | 24 | a1d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  ( 𝑘 ... 𝑚 )  =  ∅ )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 26 |  | fzn0 | ⊢ ( ( 𝑘 ... 𝑚 )  ≠  ∅  ↔  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) ) | 
						
							| 27 |  | fzfid | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 1 ... 𝑚 )  ∈  Fin ) | 
						
							| 28 |  | elfznn | ⊢ ( 𝑛  ∈  ( 1 ... 𝑚 )  →  𝑛  ∈  ℕ ) | 
						
							| 29 |  | simpr | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  𝑛  ∈  ℕ ) | 
						
							| 30 | 29 | nnrpd | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  𝑛  ∈  ℝ+ ) | 
						
							| 31 | 1 | pntrf | ⊢ 𝑅 : ℝ+ ⟶ ℝ | 
						
							| 32 | 31 | ffvelcdmi | ⊢ ( 𝑛  ∈  ℝ+  →  ( 𝑅 ‘ 𝑛 )  ∈  ℝ ) | 
						
							| 33 | 30 32 | syl | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  ( 𝑅 ‘ 𝑛 )  ∈  ℝ ) | 
						
							| 34 | 29 | peano2nnd | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  ( 𝑛  +  1 )  ∈  ℕ ) | 
						
							| 35 | 29 34 | nnmulcld | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  ( 𝑛  ·  ( 𝑛  +  1 ) )  ∈  ℕ ) | 
						
							| 36 | 33 35 | nndivred | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ℕ )  →  ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 37 | 28 36 | sylan2 | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ( 1 ... 𝑚 ) )  →  ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 38 | 27 37 | fsumrecl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 39 | 38 | recnd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℂ ) | 
						
							| 40 | 39 | abscld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ ) | 
						
							| 41 |  | fzfid | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 1 ... ( 𝑘  −  1 ) )  ∈  Fin ) | 
						
							| 42 |  | elfznn | ⊢ ( 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) )  →  𝑛  ∈  ℕ ) | 
						
							| 43 | 42 36 | sylan2 | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) )  →  ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 44 | 41 43 | fsumrecl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 45 | 44 | recnd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℂ ) | 
						
							| 46 | 45 | abscld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ ) | 
						
							| 47 |  | simplll | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑏  ∈  ℝ+ ) | 
						
							| 48 | 47 | rpred | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑏  ∈  ℝ ) | 
						
							| 49 |  | le2add | ⊢ ( ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ )  ∧  ( 𝑏  ∈  ℝ  ∧  𝑏  ∈  ℝ ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 𝑏  +  𝑏 ) ) ) | 
						
							| 50 | 40 46 48 48 49 | syl22anc | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 𝑏  +  𝑏 ) ) ) | 
						
							| 51 | 48 | recnd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑏  ∈  ℂ ) | 
						
							| 52 | 51 | 2timesd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 2  ·  𝑏 )  =  ( 𝑏  +  𝑏 ) ) | 
						
							| 53 | 52 | breq2d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 2  ·  𝑏 )  ↔  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 𝑏  +  𝑏 ) ) ) | 
						
							| 54 |  | fzfid | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 𝑘 ... 𝑚 )  ∈  Fin ) | 
						
							| 55 |  | simpllr | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑘  ∈  ℕ ) | 
						
							| 56 |  | elfzuz | ⊢ ( 𝑛  ∈  ( 𝑘 ... 𝑚 )  →  𝑛  ∈  ( ℤ≥ ‘ 𝑘 ) ) | 
						
							| 57 |  | eluznn | ⊢ ( ( 𝑘  ∈  ℕ  ∧  𝑛  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑛  ∈  ℕ ) | 
						
							| 58 | 55 56 57 | syl2an | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ( 𝑘 ... 𝑚 ) )  →  𝑛  ∈  ℕ ) | 
						
							| 59 | 58 36 | syldan | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ( 𝑘 ... 𝑚 ) )  →  ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 60 | 54 59 | fsumrecl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℝ ) | 
						
							| 61 | 60 | recnd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℂ ) | 
						
							| 62 | 55 | nnred | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑘  ∈  ℝ ) | 
						
							| 63 | 62 | ltm1d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 𝑘  −  1 )  <  𝑘 ) | 
						
							| 64 |  | fzdisj | ⊢ ( ( 𝑘  −  1 )  <  𝑘  →  ( ( 1 ... ( 𝑘  −  1 ) )  ∩  ( 𝑘 ... 𝑚 ) )  =  ∅ ) | 
						
							| 65 | 63 64 | syl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( 1 ... ( 𝑘  −  1 ) )  ∩  ( 𝑘 ... 𝑚 ) )  =  ∅ ) | 
						
							| 66 | 55 | nncnd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑘  ∈  ℂ ) | 
						
							| 67 |  | ax-1cn | ⊢ 1  ∈  ℂ | 
						
							| 68 |  | npcan | ⊢ ( ( 𝑘  ∈  ℂ  ∧  1  ∈  ℂ )  →  ( ( 𝑘  −  1 )  +  1 )  =  𝑘 ) | 
						
							| 69 | 66 67 68 | sylancl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( 𝑘  −  1 )  +  1 )  =  𝑘 ) | 
						
							| 70 | 69 55 | eqeltrd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( 𝑘  −  1 )  +  1 )  ∈  ℕ ) | 
						
							| 71 |  | nnuz | ⊢ ℕ  =  ( ℤ≥ ‘ 1 ) | 
						
							| 72 | 70 71 | eleqtrdi | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( 𝑘  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ 1 ) ) | 
						
							| 73 | 55 | nnzd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑘  ∈  ℤ ) | 
						
							| 74 | 73 13 | syl | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 𝑘  −  1 )  ∈  ℤ ) | 
						
							| 75 |  | simplr | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  𝑘  ∈  ℕ ) | 
						
							| 76 | 75 | nncnd | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  𝑘  ∈  ℂ ) | 
						
							| 77 | 76 67 68 | sylancl | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( ( 𝑘  −  1 )  +  1 )  =  𝑘 ) | 
						
							| 78 | 77 | fveq2d | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( ℤ≥ ‘ ( ( 𝑘  −  1 )  +  1 ) )  =  ( ℤ≥ ‘ 𝑘 ) ) | 
						
							| 79 | 78 | eleq2d | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( 𝑚  ∈  ( ℤ≥ ‘ ( ( 𝑘  −  1 )  +  1 ) )  ↔  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) ) ) | 
						
							| 80 | 79 | biimpar | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑚  ∈  ( ℤ≥ ‘ ( ( 𝑘  −  1 )  +  1 ) ) ) | 
						
							| 81 |  | peano2uzr | ⊢ ( ( ( 𝑘  −  1 )  ∈  ℤ  ∧  𝑚  ∈  ( ℤ≥ ‘ ( ( 𝑘  −  1 )  +  1 ) ) )  →  𝑚  ∈  ( ℤ≥ ‘ ( 𝑘  −  1 ) ) ) | 
						
							| 82 | 74 80 81 | syl2anc | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  𝑚  ∈  ( ℤ≥ ‘ ( 𝑘  −  1 ) ) ) | 
						
							| 83 |  | fzsplit2 | ⊢ ( ( ( ( 𝑘  −  1 )  +  1 )  ∈  ( ℤ≥ ‘ 1 )  ∧  𝑚  ∈  ( ℤ≥ ‘ ( 𝑘  −  1 ) ) )  →  ( 1 ... 𝑚 )  =  ( ( 1 ... ( 𝑘  −  1 ) )  ∪  ( ( ( 𝑘  −  1 )  +  1 ) ... 𝑚 ) ) ) | 
						
							| 84 | 72 82 83 | syl2anc | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 1 ... 𝑚 )  =  ( ( 1 ... ( 𝑘  −  1 ) )  ∪  ( ( ( 𝑘  −  1 )  +  1 ) ... 𝑚 ) ) ) | 
						
							| 85 | 69 | oveq1d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( 𝑘  −  1 )  +  1 ) ... 𝑚 )  =  ( 𝑘 ... 𝑚 ) ) | 
						
							| 86 | 85 | uneq2d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( 1 ... ( 𝑘  −  1 ) )  ∪  ( ( ( 𝑘  −  1 )  +  1 ) ... 𝑚 ) )  =  ( ( 1 ... ( 𝑘  −  1 ) )  ∪  ( 𝑘 ... 𝑚 ) ) ) | 
						
							| 87 | 84 86 | eqtrd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 1 ... 𝑚 )  =  ( ( 1 ... ( 𝑘  −  1 ) )  ∪  ( 𝑘 ... 𝑚 ) ) ) | 
						
							| 88 | 37 | recnd | ⊢ ( ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  ∧  𝑛  ∈  ( 1 ... 𝑚 ) )  →  ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  ∈  ℂ ) | 
						
							| 89 | 65 87 27 88 | fsumsplit | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  =  ( Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  +  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) ) | 
						
							| 90 | 45 61 89 | mvrladdd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  −  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  =  Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) | 
						
							| 91 | 90 | fveq2d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ ( Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  −  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  =  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) ) | 
						
							| 92 | 39 45 | abs2dif2d | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ ( Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) )  −  Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) ) ) | 
						
							| 93 | 91 92 | eqbrtrrd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) ) ) | 
						
							| 94 | 61 | abscld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ ) | 
						
							| 95 | 40 46 | readdcld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ∈  ℝ ) | 
						
							| 96 |  | 2re | ⊢ 2  ∈  ℝ | 
						
							| 97 | 96 | a1i | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  2  ∈  ℝ ) | 
						
							| 98 | 97 48 | remulcld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( 2  ·  𝑏 )  ∈  ℝ ) | 
						
							| 99 |  | letr | ⊢ ( ( ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ∈  ℝ  ∧  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ∈  ℝ  ∧  ( 2  ·  𝑏 )  ∈  ℝ )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ∧  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 2  ·  𝑏 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 100 | 94 95 98 99 | syl3anc | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ∧  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 2  ·  𝑏 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 101 | 93 100 | mpand | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 2  ·  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 102 | 53 101 | sylbird | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  +  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) ) )  ≤  ( 𝑏  +  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 103 | 50 102 | syld | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 104 | 103 | ancomsd | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  𝑚  ∈  ( ℤ≥ ‘ 𝑘 ) )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 105 | 26 104 | sylan2b | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  ( 𝑘 ... 𝑚 )  ≠  ∅ )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 106 | 25 105 | pm2.61dane | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  →  ( ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 107 | 106 | imp | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  𝑚  ∈  ℤ )  ∧  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 108 | 107 | an4s | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  ( 𝑚  ∈  ℤ  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 ) )  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 109 | 108 | expr | ⊢ ( ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑚  ∈  ℤ )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  →  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 110 | 109 | ralimdva | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  →  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 111 | 110 | impancom | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  𝑘  ∈  ℕ )  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  →  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 112 | 111 | an32s | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 1 ... ( 𝑘  −  1 ) ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  →  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 113 | 15 112 | mpd | ⊢ ( ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  ∧  𝑘  ∈  ℕ )  →  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 114 | 113 | ralrimiva | ⊢ ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) | 
						
							| 115 |  | breq2 | ⊢ ( 𝑐  =  ( 2  ·  𝑏 )  →  ( ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐  ↔  ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 116 | 115 | 2ralbidv | ⊢ ( 𝑐  =  ( 2  ·  𝑏 )  →  ( ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐  ↔  ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) ) ) | 
						
							| 117 | 116 | rspcev | ⊢ ( ( ( 2  ·  𝑏 )  ∈  ℝ+  ∧  ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  ( 2  ·  𝑏 ) )  →  ∃ 𝑐  ∈  ℝ+ ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐 ) | 
						
							| 118 | 5 114 117 | syl2an2r | ⊢ ( ( 𝑏  ∈  ℝ+  ∧  ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏 )  →  ∃ 𝑐  ∈  ℝ+ ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐 ) | 
						
							| 119 | 118 | rexlimiva | ⊢ ( ∃ 𝑏  ∈  ℝ+ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 1 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑏  →  ∃ 𝑐  ∈  ℝ+ ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐 ) | 
						
							| 120 | 2 119 | ax-mp | ⊢ ∃ 𝑐  ∈  ℝ+ ∀ 𝑘  ∈  ℕ ∀ 𝑚  ∈  ℤ ( abs ‘ Σ 𝑛  ∈  ( 𝑘 ... 𝑚 ) ( ( 𝑅 ‘ 𝑛 )  /  ( 𝑛  ·  ( 𝑛  +  1 ) ) ) )  ≤  𝑐 |