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%I #7 Jan 04 2024 15:34:55
%S 3,14,180,2240,21060,267988,3706920,38773952,459970056,6692483840,
%T 79425033660,800162860756,9101898907920,117326869641600,
%U 1596198064568400,20655000929239040,184885459808838660,2390210102271311936,33504016991491136160,344201347103878781440
%N Sum of the divisors of 12^n+1.
%H Max Alekseyev, <a href="/A366715/b366715.txt">Table of n, a(n) for n = 0..306</a>
%F a(n) = sigma(12^n+1) = A000203(A178248(n)).
%e a(4)=21060 because 12^4+1 has divisors {1, 89, 233, 20737}.
%p a:=n->numtheory[sigma](12^n+1):
%p seq(a(n), n=0..100);
%Y Cf. A178248, A000203, A366710, A366712, A366713, A366714, A366716, A366719, A366720, A366689.
%K nonn
%O 0,1
%A _Sean A. Irvine_, Oct 17 2023