A366682 Number of prime factors of 11^n - 1 (counted with multiplicity).

2, 5, 4, 7, 4, 9, 4, 9, 5, 8, 4, 13, 4, 8, 7, 12, 3, 12, 3, 11, 10, 11, 5, 17, 8, 10, 6, 13, 4, 15, 5, 15, 9, 9, 8, 17, 6, 10, 12, 15, 9, 17, 4, 15, 9, 12, 5, 24, 7, 14, 9, 13, 6, 16, 10, 19, 8, 10, 5, 21, 5, 12, 16, 19, 8, 22, 6, 15, 10, 19, 7, 24, 3, 11, 15

Offset: 1

Author

Sean A. Irvine, Oct 16 2023

Keywords

• nonn

Links

• Max Alekseyev, Table of n, a(n) for n = 1..316

Crossrefs

Cf. A024127, A001222, A366681, A366683, A366684, A366685, A366687.

Cf. A046051, A057958, A057957, A057956, A057955, A057954, A057953, A057952, A057951, A366708.

Programs

Mathematica

PrimeOmega[11^Range[70]-1]

PARI

a(n)=bigomega(11^n-1)

Formula

a(n) = bigomega(11^n-1) = A001222(A024127(n)).