A366708 Number of prime factors of 12^n - 1 (counted with multiplicity).

1, 2, 2, 4, 2, 5, 3, 6, 4, 4, 4, 8, 3, 6, 6, 9, 3, 9, 2, 8, 5, 6, 4, 12, 4, 8, 6, 10, 5, 13, 5, 11, 8, 6, 9, 14, 3, 6, 7, 14, 4, 14, 5, 12, 12, 8, 3, 18, 5, 10, 6, 13, 7, 16, 8, 13, 7, 8, 4, 19, 4, 8, 8, 13, 8, 17, 5, 10, 7, 14, 4, 21, 3, 7, 11, 11, 11, 18, 4

Offset: 1

Author

Sean A. Irvine, Oct 17 2023

Keywords

• nonn

Links

• Max Alekseyev, Table of n, a(n) for n = 1..310

Crossrefs

Cf. A024140, A001222, A046051, A057951, A057952, A057953, A057954, A057955, A057956, A057957, A057958, A250288, A252170, A366707, A366709, A366682.

Programs

Mathematica

PrimeOmega[12^Range[70]-1]

PARI

a(n)=bigomega(12^n-1)

Formula

a(n) = bigomega(12^n-1) = A001222(A024140(n)).