A366714 Number of divisors of 12^n+1.

2, 2, 4, 8, 4, 4, 8, 8, 8, 32, 12, 4, 16, 24, 16, 128, 4, 8, 32, 16, 64, 384, 64, 16, 64, 64, 32, 1024, 8, 8, 48, 8, 4, 512, 16, 32, 128, 16, 32, 1536, 16, 32, 64, 32, 16, 4096, 8, 32, 32, 32, 512, 512, 32, 32, 1024, 128, 512, 1536, 192, 64, 1024, 32, 64

Offset

0,1

Links

Max Alekseyev, Table of n, a(n) for n = 0..306

Formula

a(n) = sigma0(12^n+1) = A000005(A178248(n)).

Example

a(4)=4 because 12^4+1 has divisors {1, 89, 233, 20737}.

Maple

a:=n->numtheory[tau](12^n+1):
seq(a(n), n=0..100);

Prog

(PARI) a(n) = numdiv(12^n+1);

Crossrefs

Cf. A178248, A000005, A046798, A344897, A366709, A366712, A366713, A366715, A366716, A366719, A366720, A366688.

Sequence in context: A136534 A121175 A368515 * A359488 A183397 A339490

Adjacent sequences: A366711 A366712 A366713 * A366715 A366716 A366717

Keyword

nonn

Author

Sean A. Irvine, Oct 17 2023

Status

approved