| Step | Hyp | Ref | Expression | 
						
							| 1 |  | iwrdsplit.s |  | 
						
							| 2 |  | iwrdsplit.f |  | 
						
							| 3 |  | iwrdsplit.n |  | 
						
							| 4 |  | 1nn0 |  | 
						
							| 5 | 4 | a1i |  | 
						
							| 6 | 3 5 | nn0addcld |  | 
						
							| 7 | 1 2 6 | subiwrd |  | 
						
							| 8 |  | 1re |  | 
						
							| 9 |  | nn0addge2 |  | 
						
							| 10 | 8 3 9 | sylancr |  | 
						
							| 11 | 1 2 6 | subiwrdlen |  | 
						
							| 12 | 10 11 | breqtrrd |  | 
						
							| 13 |  | wrdlenge1n0 |  | 
						
							| 14 | 7 13 | syl |  | 
						
							| 15 | 12 14 | mpbird |  | 
						
							| 16 |  | pfxlswccat |  | 
						
							| 17 | 7 15 16 | syl2anc |  | 
						
							| 18 | 3 | nn0cnd |  | 
						
							| 19 |  | 1cnd |  | 
						
							| 20 | 18 19 11 | mvrraddd |  | 
						
							| 21 | 20 | oveq2d |  | 
						
							| 22 |  | nn0fz0 |  | 
						
							| 23 | 3 22 | sylib |  | 
						
							| 24 |  | elfz0add |  | 
						
							| 25 | 24 | imp |  | 
						
							| 26 | 3 5 23 25 | syl21anc |  | 
						
							| 27 | 11 | oveq2d |  | 
						
							| 28 | 26 27 | eleqtrrd |  | 
						
							| 29 |  | pfxres |  | 
						
							| 30 | 7 28 29 | syl2anc |  | 
						
							| 31 |  | fzossfzop1 |  | 
						
							| 32 |  | resabs1 |  | 
						
							| 33 | 3 31 32 | 3syl |  | 
						
							| 34 | 21 30 33 | 3eqtrd |  | 
						
							| 35 |  | lsw |  | 
						
							| 36 | 7 35 | syl |  | 
						
							| 37 | 20 | fveq2d |  | 
						
							| 38 |  | fzonn0p1 |  | 
						
							| 39 |  | fvres |  | 
						
							| 40 | 3 38 39 | 3syl |  | 
						
							| 41 | 36 37 40 | 3eqtrd |  | 
						
							| 42 | 41 | s1eqd |  | 
						
							| 43 | 34 42 | oveq12d |  | 
						
							| 44 | 17 43 | eqtr3d |  |