let D be non empty set ; for d being Element of D
for F being FinSequence of D
for g being BinOp of D st g is having_a_unity & len F = 0 holds
g "**" (F ^ <*d*>) = g . ((g "**" F),d)
let d be Element of D; for F being FinSequence of D
for g being BinOp of D st g is having_a_unity & len F = 0 holds
g "**" (F ^ <*d*>) = g . ((g "**" F),d)
let F be FinSequence of D; for g being BinOp of D st g is having_a_unity & len F = 0 holds
g "**" (F ^ <*d*>) = g . ((g "**" F),d)
let g be BinOp of D; ( g is having_a_unity & len F = 0 implies g "**" (F ^ <*d*>) = g . ((g "**" F),d) )
assume that
A1:
g is having_a_unity
and
A2:
len F = 0
; g "**" (F ^ <*d*>) = g . ((g "**" F),d)
F = <*> D
by A2;
hence g "**" (F ^ <*d*>) =
g "**" <*d*>
by FINSEQ_1:34
.=
d
by Lm4
.=
g . ((the_unity_wrt g),d)
by A1, SETWISEO:15
.=
g . ((g "**" F),d)
by A1, A2, Def1
;
verum