The On-Line Encyclopedia of Integer Sequences (OEIS)

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A366689

Sum of the divisors of 11^n+1.
(history; published version)

#7 by OEIS Server at Thu Jan 04 17:08:21 EST 2024

LINKS

Max Alekseyev, <a href="/A366689/b366689_1.txt">Table of n, a(n) for n = 0..325</a>

#6 by Max Alekseyev at Thu Jan 04 17:08:21 EST 2024

STATUS

editing

approved

Discussion

Thu Jan 04

17:08

OEIS Server: Installed first b-file as b366689.txt.

#5 by Max Alekseyev at Thu Jan 04 17:07:55 EST 2024

LINKS

Max Alekseyev, <a href="/A366689/b366689_1.txt">Table of n, a(n) for n = 0..325</a>

CROSSREFS

Cf. A034524, A000203, A366666, A366684, A366686, A366687, A366688, A366684, A366668A366690, A366715.

STATUS

approved

editing

#4 by Michael De Vlieger at Mon Oct 16 16:13:06 EDT 2023

STATUS

proposed

approved

#3 by Sean A. Irvine at Mon Oct 16 14:54:00 EDT 2023

STATUS

editing

proposed

#2 by Sean A. Irvine at Mon Oct 16 14:51:28 EDT 2023

NAME

allocated for Sean A. Irvine

Sum of the divisors of 11^n+1.

DATA

3, 28, 186, 3458, 21966, 375816, 2911272, 45470096, 340452396, 6278429920, 39543942612, 706019328000, 4708961513592, 82162955169792, 599236951715280, 11195197038864384, 68925937595777100, 1179397832668228992, 9136813499663186064, 144079834776308121600

OFFSET

0,1

FORMULA

a(n) = sigma(11^n+1) = A000203(A034524(n)).

EXAMPLE

a(4)=21966 because 11^4+1 has divisors {1, 2, 7321, 14642}.

MAPLE

a:=n->numtheory[sigma](11^n+1):

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

CROSSREFS

Cf. A034524, A000203, A366687, A366688, A366684, A366668.

KEYWORD

allocated

nonn

AUTHOR

Sean A. Irvine, Oct 16 2023

STATUS

approved

editing

#1 by Sean A. Irvine at Mon Oct 16 14:23:07 EDT 2023

NAME

allocated for Sean A. Irvine

KEYWORD

allocated

STATUS

approved