let seq1, seq2 be sequence of X; ( ( for n being Element of NAT holds seq1 . n = (Rseq . n) * (seq . n) ) & ( for n being Element of NAT holds seq2 . n = (Rseq . n) * (seq . n) ) implies seq1 = seq2 )
assume that
A1:
for n being Element of NAT holds seq1 . n = (Rseq . n) * (seq . n)
and
A2:
for n being Element of NAT holds seq2 . n = (Rseq . n) * (seq . n)
; seq1 = seq2
hence
seq1 = seq2
by FUNCT_2:113; verum