let D, D', E be non empty set ; for d1 being Element of D
for d' being Element of D'
for F being Function of [:D,D':],E
for p being FinSequence of D st p = <*d1*> holds
F [:] p,d' = <*(F . d1,d')*>
let d1 be Element of D; for d' being Element of D'
for F being Function of [:D,D':],E
for p being FinSequence of D st p = <*d1*> holds
F [:] p,d' = <*(F . d1,d')*>
let d' be Element of D'; for F being Function of [:D,D':],E
for p being FinSequence of D st p = <*d1*> holds
F [:] p,d' = <*(F . d1,d')*>
let F be Function of [:D,D':],E; for p being FinSequence of D st p = <*d1*> holds
F [:] p,d' = <*(F . d1,d')*>
let p be FinSequence of D; ( p = <*d1*> implies F [:] p,d' = <*(F . d1,d')*> )
assume A1:
p = <*d1*>
; F [:] p,d' = <*(F . d1,d')*>
A2:
p . 1 = d1
by A1, FINSEQ_1:57;
reconsider r = F [:] p,d' as FinSequence of E by Th97;
len p = 1
by A1, FINSEQ_1:56;
then A3:
len r = 1
by Th98;
then
1 in Seg (len r)
;
then
1 in dom r
by FINSEQ_1:def 3;
then
r . 1 = F . d1,d'
by A2, FUNCOP_1:35;
hence
F [:] p,d' = <*(F . d1,d')*>
by A3, FINSEQ_1:57; verum