for x1, x2, x3, x4, x5 being object
for p being FinSequence holds
( p = <*x1,x2,x3,x4,x5*> iff ( len p = 5 & p . 1 = x1 & p . 2 = x2 & p . 3 = x3 & p . 4 = x4 & p . 5 = x5 ) )