let X, Y be set ; Funcs <*X*>,Y = <*(Funcs X,Y)*>
A1:
dom <*X*> = Seg 1
by FINSEQ_1:def 8;
A2:
dom (Funcs <*X*>,Y) = dom <*X*>
by Def8;
then reconsider p = Funcs <*X*>,Y as FinSequence by A1, FINSEQ_1:def 2;
( <*X*> . 1 = X & 1 in Seg 1 )
by FINSEQ_1:4, FINSEQ_1:def 8, TARSKI:def 1;
then
p . 1 = Funcs X,Y
by A1, Def8;
hence
Funcs <*X*>,Y = <*(Funcs X,Y)*>
by A2, A1, FINSEQ_1:def 8; verum