| Step | Hyp | Ref | Expression | 
						
							| 1 |  | iprodefisumlem.1 |  | 
						
							| 2 |  | iprodefisumlem.2 |  | 
						
							| 3 |  | iprodefisumlem.3 |  | 
						
							| 4 |  | fvco3 |  | 
						
							| 5 | 3 4 | sylan |  | 
						
							| 6 | 3 | ffvelcdmda |  | 
						
							| 7 |  | efcl |  | 
						
							| 8 | 6 7 | syl |  | 
						
							| 9 | 5 8 | eqeltrd |  | 
						
							| 10 | 1 2 9 | prodf |  | 
						
							| 11 | 10 | ffnd |  | 
						
							| 12 |  | eff |  | 
						
							| 13 |  | ffn |  | 
						
							| 14 | 12 13 | ax-mp |  | 
						
							| 15 | 1 2 6 | serf |  | 
						
							| 16 |  | fnfco |  | 
						
							| 17 | 14 15 16 | sylancr |  | 
						
							| 18 |  | fveq2 |  | 
						
							| 19 |  | 2fveq3 |  | 
						
							| 20 | 18 19 | eqeq12d |  | 
						
							| 21 | 20 | imbi2d |  | 
						
							| 22 |  | fveq2 |  | 
						
							| 23 |  | 2fveq3 |  | 
						
							| 24 | 22 23 | eqeq12d |  | 
						
							| 25 | 24 | imbi2d |  | 
						
							| 26 |  | fveq2 |  | 
						
							| 27 |  | 2fveq3 |  | 
						
							| 28 | 26 27 | eqeq12d |  | 
						
							| 29 | 28 | imbi2d |  | 
						
							| 30 |  | fveq2 |  | 
						
							| 31 |  | 2fveq3 |  | 
						
							| 32 | 30 31 | eqeq12d |  | 
						
							| 33 | 32 | imbi2d |  | 
						
							| 34 |  | uzid |  | 
						
							| 35 | 2 34 | syl |  | 
						
							| 36 | 35 1 | eleqtrrdi |  | 
						
							| 37 |  | fvco3 |  | 
						
							| 38 | 3 36 37 | syl2anc |  | 
						
							| 39 |  | seq1 |  | 
						
							| 40 | 2 39 | syl |  | 
						
							| 41 |  | seq1 |  | 
						
							| 42 | 2 41 | syl |  | 
						
							| 43 | 42 | fveq2d |  | 
						
							| 44 | 38 40 43 | 3eqtr4d |  | 
						
							| 45 | 44 | a1i |  | 
						
							| 46 |  | oveq1 |  | 
						
							| 47 | 46 | 3ad2ant3 |  | 
						
							| 48 | 3 | adantl |  | 
						
							| 49 |  | peano2uz |  | 
						
							| 50 | 49 1 | eleqtrrdi |  | 
						
							| 51 | 50 | adantr |  | 
						
							| 52 |  | fvco3 |  | 
						
							| 53 | 48 51 52 | syl2anc |  | 
						
							| 54 | 53 | oveq2d |  | 
						
							| 55 | 15 | ffvelcdmda |  | 
						
							| 56 | 55 | expcom |  | 
						
							| 57 | 1 | eqcomi |  | 
						
							| 58 | 56 57 | eleq2s |  | 
						
							| 59 | 58 | imp |  | 
						
							| 60 | 48 51 | ffvelcdmd |  | 
						
							| 61 |  | efadd |  | 
						
							| 62 | 59 60 61 | syl2anc |  | 
						
							| 63 | 54 62 | eqtr4d |  | 
						
							| 64 | 63 | 3adant3 |  | 
						
							| 65 | 47 64 | eqtrd |  | 
						
							| 66 |  | seqp1 |  | 
						
							| 67 | 66 | adantr |  | 
						
							| 68 | 67 | 3adant3 |  | 
						
							| 69 |  | seqp1 |  | 
						
							| 70 | 69 | adantr |  | 
						
							| 71 | 70 | fveq2d |  | 
						
							| 72 | 71 | 3adant3 |  | 
						
							| 73 | 65 68 72 | 3eqtr4d |  | 
						
							| 74 | 73 | 3exp |  | 
						
							| 75 | 74 | a2d |  | 
						
							| 76 | 21 25 29 33 45 75 | uzind4 |  | 
						
							| 77 | 76 1 | eleq2s |  | 
						
							| 78 | 77 | impcom |  | 
						
							| 79 |  | fvco3 |  | 
						
							| 80 | 15 79 | sylan |  | 
						
							| 81 | 78 80 | eqtr4d |  | 
						
							| 82 | 11 17 81 | eqfnfvd |  |