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A366689
Sum of the divisors of 11^n+1.
12
3, 28, 186, 3458, 21966, 375816, 2911272, 45470096, 340452396, 6278429920, 39543942612, 706019328000, 4708961513592, 82162955169792, 599236951715280, 11195197038864384, 68925937595777100, 1179397832668228992, 9136813499663186064, 144079834776308121600
OFFSET
0,1
LINKS
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);
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 16 2023
STATUS
approved