OFFSET
1,4
COMMENTS
The numbers n*2^n-1 are called Woodall (or Riesel) numbers.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..865
MATHEMATICA
Table[PrimeNu[n*2^n - 1], {n, 1, 100}] (* Amiram Eldar, Dec 11 2023 *)
PROG
(PARI) a(n) = omega(n*2^n - 1); \\ Amiram Eldar, Dec 11 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 31 2023
STATUS
approved