let x1 be set ; for D, D9 being non empty set
for p being FinSequence of D
for f being Function of D,D9 st p = <*x1*> holds
f * p = <*(f . x1)*>
let D, D9 be non empty set ; for p being FinSequence of D
for f being Function of D,D9 st p = <*x1*> holds
f * p = <*(f . x1)*>
let p be FinSequence of D; for f being Function of D,D9 st p = <*x1*> holds
f * p = <*(f . x1)*>
let f be Function of D,D9; ( p = <*x1*> implies f * p = <*(f . x1)*> )
assume A1:
p = <*x1*>
; f * p = <*(f . x1)*>
A2:
p . 1 = x1
by A1, FINSEQ_1:40;
reconsider q = f * p as FinSequence of D9 by Th36;
len p = 1
by A1, FINSEQ_1:39;
then A3:
len q = 1
by Th37;
then
1 in Seg (len q)
;
then
1 in dom q
by FINSEQ_1:def 3;
then
q . 1 = f . x1
by A2, FUNCT_1:12;
hence
f * p = <*(f . x1)*>
by A3, FINSEQ_1:40; verum