OFFSET
1,1
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..502
EXAMPLE
a(3)=6 because 5^3-1 has divisors {1, 2, 4, 31, 62, 124}.
MAPLE
a:=n->numtheory[tau](5^n-1):
seq(a(n), n=1..100);
MATHEMATICA
DivisorSigma[0, 5^Range[100]-1]
PROG
(PARI) a(n) = numdiv(5^n-1);
CROSSREFS
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 14 2023
STATUS
approved