theorem Th12: :: FINSEQOP:12

for D, D9, E being non empty set
for d being Element of D
for d9 being Element of D9
for F being Function of [:D,D9:],E
for p9 being FinSequence of D9 holds F [;] (d,(p9 ^ <*d9*>)) = (F [;] (d,p9)) ^ <*(F . (d,d9))*>