OFFSET
1,2
COMMENTS
Dirichlet convolution of A061142 with itself.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
MATHEMATICA
Table[2^PrimeOmega[n] DivisorSigma[0, n], {n, 1, 75}]
f[p_, e_] := (e + 1)*2^e; a[1] = 1; a[n_] := Times @@ (f @@@ FactorInteger[n]); Array[a, 100] (* Amiram Eldar, Dec 02 2020 *)
PROG
(PARI) a(n) = numdiv(n)*2^bigomega(n); \\ Michel Marcus, Dec 02 2020
(PARI) for(n=1, 100, print1(direuler(p=2, n, 1/(1 - 2*X)^2)[n], ", ")) \\ Vaclav Kotesovec, Aug 22 2021
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Ilya Gutkovskiy, Oct 28 2019
STATUS
approved