OFFSET
1,2
COMMENTS
Number of divisors of A023887(n).
LINKS
Daniel Suteu, Table of n, a(n) for n = 1..120
EXAMPLE
a(6) = 24; The sum of the 6th powers of the divisors of 6 is 1^6 + 2^6 + 3^6 + 6^6 = 47450, which has 24 divisors. - Wesley Ivan Hurt, May 04 2021
MATHEMATICA
Table[DivisorSigma[0, DivisorSigma[w, w]], {w, 30}] (* Harvey P. Dale, Jul 08 2019 *)
PROG
(PARI) a(n) = numdiv(sigma(n, n)); \\ Michel Marcus, May 05 2021
(Python)
from math import prod
from collections import Counter
from sympy import factorint
def A064165(n): return prod(r+1 for q, r in sum((Counter(factorint((p**(n*(e+1))-1)//(p**n-1))) for p, e in factorint(n).items()), Counter()).items()) # Chai Wah Wu, Jan 28 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Sep 19 2001
EXTENSIONS
More terms from Wesley Ivan Hurt, May 04 2021
STATUS
approved