A110841 a(n) is the number of prime factors, with multiplicity, of abs(A014509(n)).

0, 0, 0, 0, 0, 0, 0, 0, 1, 4, 2, 7, 7, 2, 2, 4, 3, 3, 7, 1, 6, 4, 5, 14, 4, 9, 5, 10, 3, 11, 2, 5, 3, 7, 11, 5, 3, 4, 15, 6, 5, 19, 10, 6, 13, 15, 5, 10, 5, 5, 6, 7, 5, 15, 7, 5, 2, 13, 4, 3, 10, 5, 9, 7, 5, 4, 9, 5, 4, 1, 7, 4, 4, 5, 3, 11, 13, 10, 5, 5, 7, 6

Offset

0,10

Links

Sean A. Irvine, Table of n, a(n) for n = 0..91

Formula

a(n) = A001222(abs(A014509(n))).

Example

a(10) = 2 because A014509(10) = 529 = 23^2.
a(8) = a(19) = 1 since A014509(8) and A014509(19) are prime.

Prog

(PARI) a(n) = my(b=bernfrac(2*n), c=floor(abs(b))*sign(b)); if (c==0, 0, bigomega(c)); \\ Michel Marcus, Mar 29 2020

Crossrefs

Cf. A001222, A073276, A075178, A076547, A076549, A079294, A083687, A084217, A085092, A085737, A089170, A089644, A089655.

Sequence in context: A237750 A372860 A249652 * A128226 A049817 A203575

Adjacent sequences: A110838 A110839 A110840 * A110842 A110843 A110844

Keyword

nonn,less,more

Author

Jonathan Vos Post, Sep 16 2005

Extensions

More terms from Michel Marcus, Mar 29 2020

a(51)-a(65) from Jinyuan Wang, Apr 02 2020

More terms from Sean A. Irvine, Jul 29 2024

Status

approved