theorem Th76: :: FINSEQ_4:76
for x1, x2, x3, x4 being object
for p being FinSequence holds
( p = <*x1,x2,x3,x4*> iff ( len p = 4 & p . 1 = x1 & p . 2 = x2 & p . 3 = x3 & p . 4 = x4 ) )