The On-Line Encyclopedia of Integer Sequences (OEIS)

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A366715

Sum of the divisors of 12^n+1.
(history; published version)

#7 by OEIS Server at Thu Jan 04 15:34:55 EST 2024

LINKS

Max Alekseyev, <a href="/A366715/b366715_1.txt">Table of n, a(n) for n = 0..306</a>

#6 by Max Alekseyev at Thu Jan 04 15:34:55 EST 2024

STATUS

editing

approved

Discussion

Thu Jan 04

15:34

OEIS Server: Installed first b-file as b366715.txt.

#5 by Max Alekseyev at Thu Jan 04 15:34:51 EST 2024

LINKS

Max Alekseyev, <a href="/A366715/b366715_1.txt">Table of n, a(n) for n = 0..306</a>

CROSSREFS

Cf. A178248, A000203, A366714, A366710, A366712, A366713, A366714, A366716, A366719, A366720, A366689.

STATUS

approved

editing

#4 by Michael De Vlieger at Tue Oct 17 16:29:16 EDT 2023

STATUS

proposed

approved

#3 by Sean A. Irvine at Tue Oct 17 15:30:17 EDT 2023

STATUS

editing

proposed

#2 by Sean A. Irvine at Tue Oct 17 15:05:30 EDT 2023

NAME

allocated for Sean A. Irvine

Sum of the divisors of 12^n+1.

DATA

3, 14, 180, 2240, 21060, 267988, 3706920, 38773952, 459970056, 6692483840, 79425033660, 800162860756, 9101898907920, 117326869641600, 1596198064568400, 20655000929239040, 184885459808838660, 2390210102271311936, 33504016991491136160, 344201347103878781440

OFFSET

0,1

FORMULA

a(n) = sigma(12^n+1) = A000203(A178248(n)).

EXAMPLE

a(4)=21060 because 12^4+1 has divisors {1, 89, 233, 20737}.

MAPLE

a:=n->numtheory[sigma](12^n+1):

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

CROSSREFS

Cf. A178248, A000203, A366714, A366710, A366689.

KEYWORD

allocated

nonn

AUTHOR

Sean A. Irvine, Oct 17 2023

STATUS

approved

editing

#1 by Sean A. Irvine at Tue Oct 17 14:40:02 EDT 2023

NAME

allocated for Sean A. Irvine

KEYWORD

allocated

STATUS

approved