OFFSET
1,1
COMMENTS
LINKS
Sean A. Irvine, Table of n, a(n) for n = 1..591
FORMULA
a(n) = tau(4*(2^n -1)+1), where d(n) = A000005(n).
MATHEMATICA
Array[DivisorSigma[0, 4*(2^# - 1) + 1] &, 81] (* Michael De Vlieger, Sep 15 2021 *)
PROG
(PARI) a(n) = numdiv(4*(2^n-1) + 1); \\ Michel Marcus, Sep 16 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Edwin D. Evans, eevans2(AT)pacbell.net
EXTENSIONS
a(81) corrected by Sean A. Irvine, Sep 15 2021
STATUS
approved