OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10000
FORMULA
Multiplicative with a(p^e) = 2*((e+1)^2) - 1.
Dirichlet g.f.: zeta(s)^3 * Product_{p prime} (1 + 4/p^s - 1/p^(2*s)). - Amiram Eldar, Sep 14 2023
MATHEMATICA
Flatten[{1, Table[Product[2*((e+1)^2) - 1, {e, FactorInteger[n][[All, 2]]}], {n, 2, 100}]}] (* Vaclav Kotesovec, Sep 20 2020 *)
PROG
(PARI) A100635(n) = { my(f = factor(n), m = 1); for (k=1, #f~, m *= (2*((f[k, 2]+1)^2))-1; ); m; } \\ Antti Karttunen, May 25 2017
CROSSREFS
KEYWORD
mult,easy,nonn
AUTHOR
Vladeta Jovovic, Dec 03 2004
STATUS
approved