1,2

Table of n, a(n) for n=1..7.

For a prime p : a(p) = phi(p^3)*(p^3 - 1) = p^2*(p-1)^2*(p^2+p+1)

Cf. A086768, A053191.

Sequence in context: A320820 A160060 A115226 * A115225 A223997 A263949

Adjacent sequences: A086779 A086780 A086781 * A086783 A086784 A086785

mult,nonn

Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 03 2003

approved