A366622 - OEIS

A366622

Sum of the divisors of 6^n-1.

6, 48, 264, 1824, 9672, 67584, 335928, 2367552, 13031040, 94708224, 454285152, 3523559424, 15677418768, 113738502240, 599516366592, 4210539708672, 20465720064000, 154928015278080, 735060126170880, 5906693566844928, 26937015875831424, 188358079273592832

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OFFSET

1,1

LINKS

Max Alekseyev, Table of n, a(n) for n = 1..420

FORMULA

a(n) = sigma(6^n-1) = A000203(A024062(n)).

EXAMPLE

a(4)=1824 because 6^4-1 has divisors {1, 5, 7, 35, 37, 185, 259, 1295}.

MAPLE

a:=n->numtheory[sigma](6^n-1):

seq(a(n), n=1..100);