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A109656 Numbers n such that the sum of the digits of sum_{k=1..n}(k^k) is divisible by n. 0
1, 13, 15, 22, 25, 107, 115, 149, 163, 472, 808, 1347, 1979, 27594, 77150 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

sum_{k=1..13}(k^k) = 312086923782437; the digits of 312086923782437 sum to 65, which is divisible by 13, so 13 is in the sequence.

MATHEMATICA

s = 0; Do[s += n^n; k = Plus @@ IntegerDigits[s]; If[Mod[k, n] == 0, Print[n]], {n, 1, 10^5}]

CROSSREFS

Sequence in context: A257492 A067912 A140646 * A178724 A087814 A227449

Adjacent sequences:  A109653 A109654 A109655 * A109657 A109658 A109659

KEYWORD

nonn,base

AUTHOR

Ryan Propper, Aug 06 2005

EXTENSIONS

More terms from Ryan Propper, Nov 13 2005

STATUS

approved

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Last modified October 22 14:44 EDT 2019. Contains 328318 sequences. (Running on oeis4.)