OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Ramanujan's Papers, Some formulas in the analytic theory of numbers, Messenger of Mathematics, XLV, 1916, 81-84, Formula (15), a=b=3.
FORMULA
Dirichlet g.f.: zeta(s) * zeta(s-3)^2 * zeta(s-6) / zeta(2*s-6).
Multiplicative with a(p^e) = ((p^(3*e+3)-1)/(p^3-1))^2. - Amiram Eldar, Aug 11 2022
MATHEMATICA
Table[DivisorSigma[3, n]^2, {n, 1, 40}]
PROG
(PARI) a(n) = sigma(n, 3)^2; \\ Michel Marcus, Aug 11 2022
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Vaclav Kotesovec, Aug 11 2022
STATUS
approved