1,2

Table of n, a(n) for n=1..72.

14 = 2^1 * 7^1, a(14) = (2+7)*(1+1) = 18.

Array[Plus@@First/@FactorInteger[ # ]*Plus@@Last/@FactorInteger[ # ]&, 5! ] (* Vladimir Joseph Stephan Orlovsky, Feb 28 2010 *)

Term-wise product of A001222 and A008472.

Sequence in context: A302840 A320870 A252022 * A319131 A231566 A072620

Adjacent sequences: A039694 A039695 A039696 * A039698 A039699 A039700

nonn,easy

Olivier Gérard

approved