let S1, S2 be Series of m,L; ( ( for b being bag of m holds S1 . b = P . ((2 (#) b) +* (0,(b . 0))) ) & ( for b being bag of m holds S2 . b = P . ((2 (#) b) +* (0,(b . 0))) ) implies S1 = S2 )
assume that
A3:
for b being bag of m holds S1 . b = P . ((2 (#) b) +* (0,(b . 0)))
and
A4:
for b being bag of m holds S2 . b = P . ((2 (#) b) +* (0,(b . 0)))
; S1 = S2
for x being object st x in Bags m holds
S1 . x = S2 . x
hence
S1 = S2
; verum