| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfz2nn0 |  |-  ( K e. ( 0 ... M ) <-> ( K e. NN0 /\ M e. NN0 /\ K <_ M ) ) | 
						
							| 2 |  | simpl1 |  |-  ( ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) /\ K =/= M ) -> K e. NN0 ) | 
						
							| 3 |  | necom |  |-  ( K =/= M <-> M =/= K ) | 
						
							| 4 |  | nn0re |  |-  ( K e. NN0 -> K e. RR ) | 
						
							| 5 |  | nn0re |  |-  ( M e. NN0 -> M e. RR ) | 
						
							| 6 |  | ltlen |  |-  ( ( K e. RR /\ M e. RR ) -> ( K < M <-> ( K <_ M /\ M =/= K ) ) ) | 
						
							| 7 | 4 5 6 | syl2an |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( K < M <-> ( K <_ M /\ M =/= K ) ) ) | 
						
							| 8 | 7 | bicomd |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( ( K <_ M /\ M =/= K ) <-> K < M ) ) | 
						
							| 9 |  | elnn0z |  |-  ( K e. NN0 <-> ( K e. ZZ /\ 0 <_ K ) ) | 
						
							| 10 |  | 0red |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> 0 e. RR ) | 
						
							| 11 |  | zre |  |-  ( K e. ZZ -> K e. RR ) | 
						
							| 12 | 11 | adantr |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> K e. RR ) | 
						
							| 13 | 5 | adantl |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> M e. RR ) | 
						
							| 14 |  | lelttr |  |-  ( ( 0 e. RR /\ K e. RR /\ M e. RR ) -> ( ( 0 <_ K /\ K < M ) -> 0 < M ) ) | 
						
							| 15 | 10 12 13 14 | syl3anc |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> ( ( 0 <_ K /\ K < M ) -> 0 < M ) ) | 
						
							| 16 |  | nn0z |  |-  ( M e. NN0 -> M e. ZZ ) | 
						
							| 17 |  | elnnz |  |-  ( M e. NN <-> ( M e. ZZ /\ 0 < M ) ) | 
						
							| 18 | 17 | simplbi2 |  |-  ( M e. ZZ -> ( 0 < M -> M e. NN ) ) | 
						
							| 19 | 16 18 | syl |  |-  ( M e. NN0 -> ( 0 < M -> M e. NN ) ) | 
						
							| 20 | 19 | adantl |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> ( 0 < M -> M e. NN ) ) | 
						
							| 21 | 15 20 | syld |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> ( ( 0 <_ K /\ K < M ) -> M e. NN ) ) | 
						
							| 22 | 21 | expd |  |-  ( ( K e. ZZ /\ M e. NN0 ) -> ( 0 <_ K -> ( K < M -> M e. NN ) ) ) | 
						
							| 23 | 22 | impancom |  |-  ( ( K e. ZZ /\ 0 <_ K ) -> ( M e. NN0 -> ( K < M -> M e. NN ) ) ) | 
						
							| 24 | 9 23 | sylbi |  |-  ( K e. NN0 -> ( M e. NN0 -> ( K < M -> M e. NN ) ) ) | 
						
							| 25 | 24 | imp |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( K < M -> M e. NN ) ) | 
						
							| 26 | 8 25 | sylbid |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( ( K <_ M /\ M =/= K ) -> M e. NN ) ) | 
						
							| 27 | 26 | expd |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( K <_ M -> ( M =/= K -> M e. NN ) ) ) | 
						
							| 28 | 3 27 | syl7bi |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( K <_ M -> ( K =/= M -> M e. NN ) ) ) | 
						
							| 29 | 28 | 3impia |  |-  ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) -> ( K =/= M -> M e. NN ) ) | 
						
							| 30 | 29 | imp |  |-  ( ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) /\ K =/= M ) -> M e. NN ) | 
						
							| 31 | 8 | biimpd |  |-  ( ( K e. NN0 /\ M e. NN0 ) -> ( ( K <_ M /\ M =/= K ) -> K < M ) ) | 
						
							| 32 | 31 | exp4b |  |-  ( K e. NN0 -> ( M e. NN0 -> ( K <_ M -> ( M =/= K -> K < M ) ) ) ) | 
						
							| 33 | 32 | 3imp |  |-  ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) -> ( M =/= K -> K < M ) ) | 
						
							| 34 | 3 33 | biimtrid |  |-  ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) -> ( K =/= M -> K < M ) ) | 
						
							| 35 | 34 | imp |  |-  ( ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) /\ K =/= M ) -> K < M ) | 
						
							| 36 | 2 30 35 | 3jca |  |-  ( ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) /\ K =/= M ) -> ( K e. NN0 /\ M e. NN /\ K < M ) ) | 
						
							| 37 | 36 | ex |  |-  ( ( K e. NN0 /\ M e. NN0 /\ K <_ M ) -> ( K =/= M -> ( K e. NN0 /\ M e. NN /\ K < M ) ) ) | 
						
							| 38 | 1 37 | sylbi |  |-  ( K e. ( 0 ... M ) -> ( K =/= M -> ( K e. NN0 /\ M e. NN /\ K < M ) ) ) | 
						
							| 39 | 38 | impcom |  |-  ( ( K =/= M /\ K e. ( 0 ... M ) ) -> ( K e. NN0 /\ M e. NN /\ K < M ) ) | 
						
							| 40 |  | elfzo0 |  |-  ( K e. ( 0 ..^ M ) <-> ( K e. NN0 /\ M e. NN /\ K < M ) ) | 
						
							| 41 | 39 40 | sylibr |  |-  ( ( K =/= M /\ K e. ( 0 ... M ) ) -> K e. ( 0 ..^ M ) ) |