A366617 - OEIS

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A366617

Sum of the divisors of 5^n+1.

3, 12, 42, 312, 942, 6264, 25284, 162000, 620460, 4961280, 16161768, 103442688, 367381884, 2441936064, 9859525284, 76963663296, 228970112844, 1526377433328, 6339280635408, 38199227335200, 144103649734968, 1285221510144000, 3894650946433800, 24349131482713344

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OFFSET

0,1

LINKS

Max Alekseyev, Table of n, a(n) for n = 0..471

FORMULA

a(n) = sigma(5^n+1) = A000203(A034474(n)).

EXAMPLE

a(3)=312 because 5^3+1 has divisors {1, 2, 3, 6, 7, 9, 14, 18, 21, 42, 63, 126}.

MAPLE

a:=n->numtheory[sigma](5^n+1):

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