A366714 - OEIS

%I #7 Jan 04 2024 15:33:12

%S 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,

%T 32,1024,8,8,48,8,4,512,16,32,128,16,32,1536,16,32,64,32,16,4096,8,32,

%U 32,32,512,512,32,32,1024,128,512,1536,192,64,1024,32,64

%N Number of divisors of 12^n+1.

%H Max Alekseyev, <a href="/A366714/b366714.txt">Table of n, a(n) for n = 0..306</a>

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

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

%p a:=n->numtheory[tau](12^n+1):

%p seq(a(n), n=0..100);

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

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

%K nonn

%O 0,1

%A _Sean A. Irvine_, Oct 17 2023