answersLogoWhite

0

It is easy to rush into this one and claim that it is "add 5". But that overlooks the fact that 20 and 25 do not feature in the pattern.

There are infinitely many possible answers. One of these is the polynomial:

Un = (n5 - 20n4 + 145n3 - 460n2 + 664n - 300)/6 for n = 1, 2, 3, ...

User Avatar

Wiki User

12y ago

What else can I help you with?