A068477 a(n) is the digital sum of 1^n + 2^n + ... + n^n.

0, 1, 5, 9, 12, 15, 22, 10, 33, 45, 43, 60, 44, 79, 70, 72, 65, 90, 111, 91, 125, 117, 132, 168, 133, 127, 171, 189, 172, 195, 218, 232, 217, 234, 221, 243, 240, 280, 290, 261, 315, 348, 352, 325, 345, 351, 346, 303, 338, 367, 373, 396, 404, 414, 495, 424, 428

Offset: 0

Author

Francois Jooste (phukraut(AT)hotmail.com), Mar 10 2002

Keywords

• nonn
• base

Links

• G. C. Greubel, Table of n, a(n) for n = 0..1000

Programs

Maple

dig := X->convert((convert(X,base,10)),`+`); a := n->dig(sum(m^n,m=1..n));

Mathematica

Table[Sum[DigitCount[Sum[k^n, {k, 1, n}]][[i]]*i, {i, 9}], {n, 0, 100}] (* G. C. Greubel, Oct 13 2018 *)

PARI

a(n) = sumdigits(sum(k=1, n, k^n)); \\ Michel Marcus, Oct 14 2018

Formula

a(n) = A007953(A031971(n))