Theorem expvalt 4677

Description: Value of exponentiation to natural number powers. NN X. {A} is the constant function with value A. The seq operation produces the sequence A, A x. A, (A x. A) x. A,... that we evaluate at index B.

Assertion

Ref	Expression
expvalt	|- ((A e. CC /\ B e. NN) -> (A^B) = (( x. seq(NN X. {A}))` B))

Proof of Theorem expvalt

Step	Hyp	Ref	Expression
1		fvex 2838	. 2 |- (( x. seq(NN X. {A}))` B) e. V
2		sneq 1816	. . . . 5 |- (x = A -> {x} = {A})
3		xpeq2 2441	. . . . 5 |- ({x} = {A} -> (NN X. {x}) = (NN X. {A}))
4	2, 3	syl 12	. . . 4 |- (x = A -> (NN X. {x}) = (NN X. {A}))
5	4	opreq2d 3013	. . 3 |- (x = A -> ( x. seq(NN X. {x})) = ( x. seq(NN X. {A})))
6	5	fveq1d 2834	. 2 |- (x = A -> (( x. seq(NN X. {x}))` y) = (( x. seq(NN X. {A}))` y))
7		fveq2 2832	. 2 |- (y = B -> (( x. seq(NN X. {A}))` y) = (( x. seq(NN X. {A}))` B))
8		df-exp 4676	. 2 |- ^ = {<.<.x, y>., z>. | ((x e. CC /\ y e. NN) /\ z = (( x. seq(NN X. {x}))` y))}
9	1, 6, 7, 8	oprabval2 3051	1 |- ((A e. CC /\ B e. NN) -> (A^B) = (( x. seq(NN X. {A}))` B))

Syntax hints:   -> wi 2   /\ wa 196   = wceq 1091   e. wcel 1092  {csn 1808   X. cxp 2408  ` cfv 2422  (class class class)co 3001  CCcc 4026   x. cmulc 4032  NNcn 4093  seqcseq 4660  ^cexp 4675

This theorem is referenced by:  expp1t 4678  exp1t 4679

This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-13 804  ax-14 805  ax-16 922  ax-17 925  ax-ext 1074  ax-rep 1075  ax-un 1076  ax-pow 1077

This theorem depends on definitions:  df-bi 128  df-or 197  df-an 198  df-3an 583  df-ex 679  df-sb 853  df-eu 1009  df-mo 1010  df-clab 1093  df-cleq 1097  df-clel 1099  df-rex 1206  df-v 1349  df-dif 1489  df-un 1490  df-in 1491  df-ss 1492  df-nul 1708  df-pw 1799  df-sn 1811  df-pr 1812  df-op 1815  df-uni 1920  df-br 2063  df-opab 2098  df-id 2125  df-xp 2424  df-rel 2425  df-cnv 2426  df-co 2427  df-dm 2428  df-rn 2429  df-res 2430  df-ima 2431  df-fun 2432  df-fv 2438  df-opr 3003  df-oprab 3004  df-exp 4676

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