Theorem hashfibc 11266

Description: The binomial coefficient counts the number of subsets of a finite set of a given size. This is Metamath 100 proof #58 (formula for the number of combinations). For more on the notation for subsets of a given size, see sseqn 11262. (Contributed by Mario Carneiro, 13-Jul-2014.)

Assertion

Ref	Expression
hashfibc	|- ( ( A e. Fin /\ K e. ZZ ) -> ( (♯ ` A ) _C K ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } ) )

Distinct variable groups:   x, A   x, K

Proof of Theorem hashfibc

Dummy variables k w y z j are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		fveq2 5693	. . . . . 6 |- ( w = (/) -> (♯ ` w ) = (♯ ` (/) ) )
2	1	oveq1d 6094	. . . . 5 |- ( w = (/) -> ( (♯ ` w ) _C k ) = ( (♯ ` (/) ) _C k ) )
3		pweq 3691	. . . . . . . 8 |- ( w = (/) -> ~P w = ~P (/) )
4	3	ineq1d 3431	. . . . . . 7 |- ( w = (/) -> ( ~P w i^i Fin ) = ( ~P (/) i^i Fin ) )
5	4	rabeqdv 2815	. . . . . 6 |- ( w = (/) -> { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } )
6	5	fveq2d 5697	. . . . 5 |- ( w = (/) -> (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } ) )
7	2, 6	eqeq12d 2253	. . . 4 |- ( w = (/) -> ( ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } ) ) )
8	7	ralbidv 2550	. . 3 |- ( w = (/) -> ( A. k e. ZZ ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> A. k e. ZZ ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } ) ) )
9		fveq2 5693	. . . . . 6 |- ( w = y -> (♯ ` w ) = (♯ ` y ) )
10	9	oveq1d 6094	. . . . 5 |- ( w = y -> ( (♯ ` w ) _C k ) = ( (♯ ` y ) _C k ) )
11		pweq 3691	. . . . . . . 8 |- ( w = y -> ~P w = ~P y )
12	11	ineq1d 3431	. . . . . . 7 |- ( w = y -> ( ~P w i^i Fin ) = ( ~P y i^i Fin ) )
13	12	rabeqdv 2815	. . . . . 6 |- ( w = y -> { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } )
14	13	fveq2d 5697	. . . . 5 |- ( w = y -> (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) )
15	10, 14	eqeq12d 2253	. . . 4 |- ( w = y -> ( ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` y ) _C k ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) ) )
16	15	ralbidv 2550	. . 3 |- ( w = y -> ( A. k e. ZZ ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> A. k e. ZZ ( (♯ ` y ) _C k ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) ) )
17		fveq2 5693	. . . . . 6 |- ( w = ( y u. { z } ) -> (♯ ` w ) = (♯ ` ( y u. { z } ) ) )
18	17	oveq1d 6094	. . . . 5 |- ( w = ( y u. { z } ) -> ( (♯ ` w ) _C k ) = ( (♯ ` ( y u. { z } ) ) _C k ) )
19		pweq 3691	. . . . . . . 8 |- ( w = ( y u. { z } ) -> ~P w = ~P ( y u. { z } ) )
20	19	ineq1d 3431	. . . . . . 7 |- ( w = ( y u. { z } ) -> ( ~P w i^i Fin ) = ( ~P ( y u. { z } ) i^i Fin ) )
21	20	rabeqdv 2815	. . . . . 6 |- ( w = ( y u. { z } ) -> { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } )
22	21	fveq2d 5697	. . . . 5 |- ( w = ( y u. { z } ) -> (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) )
23	18, 22	eqeq12d 2253	. . . 4 |- ( w = ( y u. { z } ) -> ( ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) ) )
24	23	ralbidv 2550	. . 3 |- ( w = ( y u. { z } ) -> ( A. k e. ZZ ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> A. k e. ZZ ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) ) )
25		fveq2 5693	. . . . . 6 |- ( w = A -> (♯ ` w ) = (♯ ` A ) )
26	25	oveq1d 6094	. . . . 5 |- ( w = A -> ( (♯ ` w ) _C k ) = ( (♯ ` A ) _C k ) )
27		pweq 3691	. . . . . . . 8 |- ( w = A -> ~P w = ~P A )
28	27	ineq1d 3431	. . . . . . 7 |- ( w = A -> ( ~P w i^i Fin ) = ( ~P A i^i Fin ) )
29	28	rabeqdv 2815	. . . . . 6 |- ( w = A -> { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } )
30	29	fveq2d 5697	. . . . 5 |- ( w = A -> (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) )
31	26, 30	eqeq12d 2253	. . . 4 |- ( w = A -> ( ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` A ) _C k ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) ) )
32	31	ralbidv 2550	. . 3 |- ( w = A -> ( A. k e. ZZ ( (♯ ` w ) _C k ) = (♯ ` { x e. ( ~P w i^i Fin ) | (♯ ` x ) = k } ) <-> A. k e. ZZ ( (♯ ` A ) _C k ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) ) )
33		0nn0 9561	. . . . . . . . 9 |- 0 e. NN0
34		bcn0 11176	. . . . . . . . 9 |- ( 0 e. NN0 -> ( 0 _C 0 ) = 1 )
35	33, 34	ax-mp 5	. . . . . . . 8 |- ( 0 _C 0 ) = 1
36		hash0 11218	. . . . . . . . . 10 |- (♯ ` (/) ) = 0
37	36	a1i 9	. . . . . . . . 9 |- ( k e. ( 0 ... 0 ) -> (♯ ` (/) ) = 0 )
38		elfz1eq 10422	. . . . . . . . 9 |- ( k e. ( 0 ... 0 ) -> k = 0 )
39	37, 38	oveq12d 6097	. . . . . . . 8 |- ( k e. ( 0 ... 0 ) -> ( (♯ ` (/) ) _C k ) = ( 0 _C 0 ) )
40	38	eqcomd 2244	. . . . . . . . . . . . 13 |- ( k e. ( 0 ... 0 ) -> 0 = k )
41		pw0 3860	. . . . . . . . . . . . . . 15 |- ~P (/) = { (/) }
42	41	raleqi 2753	. . . . . . . . . . . . . 14 |- ( A. x e. ~P (/) (♯ ` x ) = k <-> A. x e. { (/) } (♯ ` x ) = k )
43		0ex 4258	. . . . . . . . . . . . . . 15 |- (/) e. _V
44		fveq2 5693	. . . . . . . . . . . . . . . . 17 |- ( x = (/) -> (♯ ` x ) = (♯ ` (/) ) )
45	44, 36	eqtrdi 2287	. . . . . . . . . . . . . . . 16 |- ( x = (/) -> (♯ ` x ) = 0 )
46	45	eqeq1d 2247	. . . . . . . . . . . . . . 15 |- ( x = (/) -> ( (♯ ` x ) = k <-> 0 = k ) )
47	43, 46	ralsn 3751	. . . . . . . . . . . . . 14 |- ( A. x e. { (/) } (♯ ` x ) = k <-> 0 = k )
48	42, 47	bitri 184	. . . . . . . . . . . . 13 |- ( A. x e. ~P (/) (♯ ` x ) = k <-> 0 = k )
49	40, 48	sylibr 134	. . . . . . . . . . . 12 |- ( k e. ( 0 ... 0 ) -> A. x e. ~P (/) (♯ ` x ) = k )
50		rabid2 2729	. . . . . . . . . . . 12 |- ( ~P (/) = { x e. ~P (/) | (♯ ` x ) = k } <-> A. x e. ~P (/) (♯ ` x ) = k )
51	49, 50	sylibr 134	. . . . . . . . . . 11 |- ( k e. ( 0 ... 0 ) -> ~P (/) = { x e. ~P (/) | (♯ ` x ) = k } )
52	51, 41	eqtr3di 2286	. . . . . . . . . 10 |- ( k e. ( 0 ... 0 ) -> { x e. ~P (/) | (♯ ` x ) = k } = { (/) } )
53	52	fveq2d 5697	. . . . . . . . 9 |- ( k e. ( 0 ... 0 ) -> (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) = (♯ ` { (/) } ) )
54		hashsng 11220	. . . . . . . . . 10 |- ( (/) e. _V -> (♯ ` { (/) } ) = 1 )
55	43, 54	ax-mp 5	. . . . . . . . 9 |- (♯ ` { (/) } ) = 1
56	53, 55	eqtrdi 2287	. . . . . . . 8 |- ( k e. ( 0 ... 0 ) -> (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) = 1 )
57	35, 39, 56	3eqtr4a 2297	. . . . . . 7 |- ( k e. ( 0 ... 0 ) -> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) )
58	57	adantl 277	. . . . . 6 |- ( ( k e. ZZ /\ k e. ( 0 ... 0 ) ) -> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) )
59	36	oveq1i 6089	. . . . . . 7 |- ( (♯ ` (/) ) _C k ) = ( 0 _C k )
60		bcval3 11172	. . . . . . . . 9 |- ( ( 0 e. NN0 /\ k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> ( 0 _C k ) = 0 )
61	33, 60	mp3an1 1365	. . . . . . . 8 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> ( 0 _C k ) = 0 )
62		id 19	. . . . . . . . . . . . . . 15 |- ( 0 = k -> 0 = k )
63		0z 9638	. . . . . . . . . . . . . . . 16 |- 0 e. ZZ
64		elfz3 10421	. . . . . . . . . . . . . . . 16 |- ( 0 e. ZZ -> 0 e. ( 0 ... 0 ) )
65	63, 64	ax-mp 5	. . . . . . . . . . . . . . 15 |- 0 e. ( 0 ... 0 )
66	62, 65	eqeltrrdi 2330	. . . . . . . . . . . . . 14 |- ( 0 = k -> k e. ( 0 ... 0 ) )
67	66	con3i 641	. . . . . . . . . . . . 13 |- ( -. k e. ( 0 ... 0 ) -> -. 0 = k )
68	67	adantl 277	. . . . . . . . . . . 12 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> -. 0 = k )
69	41	raleqi 2753	. . . . . . . . . . . . 13 |- ( A. x e. ~P (/) -. (♯ ` x ) = k <-> A. x e. { (/) } -. (♯ ` x ) = k )
70	46	notbid 677	. . . . . . . . . . . . . 14 |- ( x = (/) -> ( -. (♯ ` x ) = k <-> -. 0 = k ) )
71	43, 70	ralsn 3751	. . . . . . . . . . . . 13 |- ( A. x e. { (/) } -. (♯ ` x ) = k <-> -. 0 = k )
72	69, 71	bitri 184	. . . . . . . . . . . 12 |- ( A. x e. ~P (/) -. (♯ ` x ) = k <-> -. 0 = k )
73	68, 72	sylibr 134	. . . . . . . . . . 11 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> A. x e. ~P (/) -. (♯ ` x ) = k )
74		rabeq0 3552	. . . . . . . . . . 11 |- ( { x e. ~P (/) | (♯ ` x ) = k } = (/) <-> A. x e. ~P (/) -. (♯ ` x ) = k )
75	73, 74	sylibr 134	. . . . . . . . . 10 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> { x e. ~P (/) | (♯ ` x ) = k } = (/) )
76	75	fveq2d 5697	. . . . . . . . 9 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) = (♯ ` (/) ) )
77	76, 36	eqtrdi 2287	. . . . . . . 8 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) = 0 )
78	61, 77	eqtr4d 2274	. . . . . . 7 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> ( 0 _C k ) = (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) )
79	59, 78	eqtrid 2283	. . . . . 6 |- ( ( k e. ZZ /\ -. k e. ( 0 ... 0 ) ) -> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) )
80		0zd 9639	. . . . . . . 8 |- ( k e. ZZ -> 0 e. ZZ )
81		fzdcel 10427	. . . . . . . 8 |- ( ( k e. ZZ /\ 0 e. ZZ /\ 0 e. ZZ ) -> DECID k e. ( 0 ... 0 ) )
82	80, 80, 81	mpd3an23 1380	. . . . . . 7 |- ( k e. ZZ -> DECID k e. ( 0 ... 0 ) )
83		exmiddc 848	. . . . . . 7 |- (DECID k e. ( 0 ... 0 ) -> ( k e. ( 0 ... 0 ) \/ -. k e. ( 0 ... 0 ) ) )
84	82, 83	syl 14	. . . . . 6 |- ( k e. ZZ -> ( k e. ( 0 ... 0 ) \/ -. k e. ( 0 ... 0 ) ) )
85	58, 79, 84	mpjaodan 810	. . . . 5 |- ( k e. ZZ -> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) )
86		velsn 3725	. . . . . . . . . . 11 |- ( x e. { (/) } <-> x = (/) )
87		0fi 7182	. . . . . . . . . . . 12 |- (/) e. Fin
88		eleq1 2301	. . . . . . . . . . . 12 |- ( x = (/) -> ( x e. Fin <-> (/) e. Fin ) )
89	87, 88	mpbiri 168	. . . . . . . . . . 11 |- ( x = (/) -> x e. Fin )
90	86, 89	sylbi 121	. . . . . . . . . 10 |- ( x e. { (/) } -> x e. Fin )
91	90, 41	eleq2s 2333	. . . . . . . . 9 |- ( x e. ~P (/) -> x e. Fin )
92	91	ssriv 3252	. . . . . . . 8 |- ~P (/) C_ Fin
93		dfss 3234	. . . . . . . 8 |- ( ~P (/) C_ Fin <-> ~P (/) = ( ~P (/) i^i Fin ) )
94	92, 93	mpbi 145	. . . . . . 7 |- ~P (/) = ( ~P (/) i^i Fin )
95	94	rabeqi 2814	. . . . . 6 |- { x e. ~P (/) | (♯ ` x ) = k } = { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k }
96	95	fveq2i 5696	. . . . 5 |- (♯ ` { x e. ~P (/) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } )
97	85, 96	eqtrdi 2287	. . . 4 |- ( k e. ZZ -> ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } ) )
98	97	rgen 2603	. . 3 |- A. k e. ZZ ( (♯ ` (/) ) _C k ) = (♯ ` { x e. ( ~P (/) i^i Fin ) | (♯ ` x ) = k } )
99		oveq2 6087	. . . . . 6 |- ( k = j -> ( (♯ ` y ) _C k ) = ( (♯ ` y ) _C j ) )
100		eqeq2 2248	. . . . . . . . 9 |- ( k = j -> ( (♯ ` x ) = k <-> (♯ ` x ) = j ) )
101	100	rabbidv 2810	. . . . . . . 8 |- ( k = j -> { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } )
102		fveqeq2 5702	. . . . . . . . 9 |- ( x = z -> ( (♯ ` x ) = j <-> (♯ ` z ) = j ) )
103	102	cbvrabv 2820	. . . . . . . 8 |- { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } = { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j }
104	101, 103	eqtrdi 2287	. . . . . . 7 |- ( k = j -> { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } = { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } )
105	104	fveq2d 5697	. . . . . 6 |- ( k = j -> (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) )
106	99, 105	eqeq12d 2253	. . . . 5 |- ( k = j -> ( ( (♯ ` y ) _C k ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) )
107	106	cbvralvw 2790	. . . 4 |- ( A. k e. ZZ ( (♯ ` y ) _C k ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) <-> A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) )
108		simpll 531	. . . . . . 7 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> y e. Fin )
109		simplr 533	. . . . . . 7 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> -. z e. y )
110		simprr 537	. . . . . . . 8 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) )
111	103	fveq2i 5696	. . . . . . . . . 10 |- (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } )
112	111	eqeq2i 2249	. . . . . . . . 9 |- ( ( (♯ ` y ) _C j ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } ) <-> ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) )
113	112	ralbii 2556	. . . . . . . 8 |- ( A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } ) <-> A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) )
114	110, 113	sylibr 134	. . . . . . 7 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = j } ) )
115		simprl 535	. . . . . . 7 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> k e. ZZ )
116	108, 109, 114, 115	hashfibclem 11265	. . . . . 6 |- ( ( ( y e. Fin /\ -. z e. y ) /\ ( k e. ZZ /\ A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) ) ) -> ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) )
117	116	expr 375	. . . . 5 |- ( ( ( y e. Fin /\ -. z e. y ) /\ k e. ZZ ) -> ( A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) -> ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) ) )
118	117	ralrimdva 2630	. . . 4 |- ( ( y e. Fin /\ -. z e. y ) -> ( A. j e. ZZ ( (♯ ` y ) _C j ) = (♯ ` { z e. ( ~P y i^i Fin ) | (♯ ` z ) = j } ) -> A. k e. ZZ ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) ) )
119	107, 118	biimtrid 152	. . 3 |- ( ( y e. Fin /\ -. z e. y ) -> ( A. k e. ZZ ( (♯ ` y ) _C k ) = (♯ ` { x e. ( ~P y i^i Fin ) | (♯ ` x ) = k } ) -> A. k e. ZZ ( (♯ ` ( y u. { z } ) ) _C k ) = (♯ ` { x e. ( ~P ( y u. { z } ) i^i Fin ) | (♯ ` x ) = k } ) ) )
120	8, 16, 24, 32, 98, 119	findcard2s 7188	. 2 |- ( A e. Fin -> A. k e. ZZ ( (♯ ` A ) _C k ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) )
121		oveq2 6087	. . . 4 |- ( k = K -> ( (♯ ` A ) _C k ) = ( (♯ ` A ) _C K ) )
122		eqeq2 2248	. . . . . 6 |- ( k = K -> ( (♯ ` x ) = k <-> (♯ ` x ) = K ) )
123	122	rabbidv 2810	. . . . 5 |- ( k = K -> { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } = { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } )
124	123	fveq2d 5697	. . . 4 |- ( k = K -> (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } ) )
125	121, 124	eqeq12d 2253	. . 3 |- ( k = K -> ( ( (♯ ` A ) _C k ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) <-> ( (♯ ` A ) _C K ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } ) ) )
126	125	rspccva 2928	. 2 |- ( ( A. k e. ZZ ( (♯ ` A ) _C k ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = k } ) /\ K e. ZZ ) -> ( (♯ ` A ) _C K ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } ) )
127	120, 126	sylan 283	1 |- ( ( A e. Fin /\ K e. ZZ ) -> ( (♯ ` A ) _C K ) = (♯ ` { x e. ( ~P A i^i Fin ) | (♯ ` x ) = K } ) )

Syntax hints:   -. wn 3   -> wi 4   /\ wa 104   \/ wo 720  DECID wdc 846   = wceq 1402   e. wcel 2209   A.wral 2528   {crab 2532   _Vcvv 2821   u. cun 3218   i^i cin 3219   C_ wss 3220   (/)c0 3520   ~Pcpw 3688   {csn 3708   ` cfv 5375  (class class class)co 6079   Fincfn 7016   0cc0 8173   1c1 8174   NN0cn0 9546   ZZcz 9627   ...cfz 10394   _C cbc 11168  ♯chash 11197

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-13 2211  ax-14 2212  ax-ext 2220  ax-coll 4244  ax-sep 4247  ax-nul 4257  ax-pow 4309  ax-pr 4344  ax-un 4576  ax-setind 4682  ax-iinf 4733  ax-cnex 8264  ax-resscn 8265  ax-1cn 8266  ax-1re 8267  ax-icn 8268  ax-addcl 8269  ax-addrcl 8270  ax-mulcl 8271  ax-mulrcl 8272  ax-addcom 8273  ax-mulcom 8274  ax-addass 8275  ax-mulass 8276  ax-distr 8277  ax-i2m1 8278  ax-0lt1 8279  ax-1rid 8280  ax-0id 8281  ax-rnegex 8282  ax-precex 8283  ax-cnre 8284  ax-pre-ltirr 8285  ax-pre-ltwlin 8286  ax-pre-lttrn 8287  ax-pre-apti 8288  ax-pre-ltadd 8289  ax-pre-mulgt0 8290  ax-pre-mulext 8291

This theorem depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rmo 2536  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-if 3639  df-pw 3690  df-sn 3714  df-pr 3715  df-op 3717  df-uni 3934  df-int 3969  df-iun 4012  df-br 4129  df-opab 4191  df-mpt 4192  df-tr 4228  df-id 4436  df-po 4439  df-iso 4440  df-iord 4509  df-on 4511  df-ilim 4512  df-suc 4514  df-iom 4736  df-xp 4778  df-rel 4779  df-cnv 4780  df-co 4781  df-dm 4782  df-rn 4783  df-res 4784  df-ima 4785  df-iota 5335  df-fun 5377  df-fn 5378  df-f 5379  df-f1 5380  df-fo 5381  df-f1o 5382  df-fv 5383  df-riota 6032  df-ov 6082  df-oprab 6083  df-mpo 6084  df-1st 6368  df-2nd 6369  df-recs 6570  df-irdg 6635  df-frec 6656  df-1o 6681  df-2o 6682  df-oadd 6685  df-er 6801  df-map 6918  df-en 7017  df-dom 7018  df-fin 7019  df-pnf 8356  df-mnf 8357  df-xr 8358  df-ltxr 8359  df-le 8360  df-sub 8493  df-neg 8494  df-reap 8897  df-ap 8904  df-div 8997  df-inn 9288  df-n0 9547  df-z 9628  df-uz 9905  df-q 10003  df-rp 10038  df-fz 10395  df-seqfrec 10868  df-fac 11147  df-bc 11169  df-ihash 11198

This theorem is referenced by:  ballotfilem1  13203  ballotfilem2  13211