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A345895
a(n) = Sum_{d|n} n^sigma(d).
3
1, 10, 84, 16452, 15630, 2176783854, 5764808, 35184374186504, 2541865834899, 1000000000001001010, 3138428376732, 1648446623609512552867179993036, 3937376385699302, 3214199700417740938226879430, 16834112196028232574474331890, 21267647932558653967613834469360799760
OFFSET
1,2
LINKS
FORMULA
a(prime(n)) = A104128(n). - Michel Marcus, Jun 29 2021
EXAMPLE
a(4) = Sum_{d|4} 4^sigma(d) = 4^1 + 4^3 + 4^7 = 16452.
MATHEMATICA
a[n_] := DivisorSum[n, n^DivisorSigma[1, #] &]; Array[a, 16] (* Amiram Eldar, Jun 29 2021 *)
PROG
(PARI) a(n) = sumdiv(n, d, n^sigma(d)); \\ Michel Marcus, Jun 29 2021
CROSSREFS
Cf. A000203 (sigma), A104128, A174472, A345271.
Sequence in context: A350903 A318793 A104128 * A014341 A323970 A253009
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jun 28 2021
STATUS
approved