A124359 - OEIS

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A124359

Numbers n for which the sum of the digits of n^k, for some k, is equal to n.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 17, 18, 20, 22, 25, 26, 27, 28, 31, 34, 35, 36, 40, 43, 45, 46, 53, 54, 58, 63, 64, 68, 71, 80, 81, 82, 85, 86, 90, 91, 94, 97, 98, 103, 104, 106, 107, 108, 117, 118, 126, 127, 133, 134, 135, 136, 140, 142, 143, 146, 152, 154, 155, 157, 160, 163, 169, 170

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OFFSET

1,3

COMMENTS

Most of the values are conjectural. So far not much is proved about the function A247889. - M. F. Hasler and Robert Israel, May 18 2017

LINKS

Hans Havermann, Table of n, a(n) for n = 1..3600

Hans Havermann, Solutions (k) for the terms (n <= 20034) of this sequence

EXAMPLE

18^3 = 5832 and 5 + 8 + 3 + 2 = 18 (also 18^6 = 34012224 and 18^7 = 612220032).

Again 46^5 = 205962976 and 2 + 0 + 5 + 9 + 6 + 2 + 9 + 7 + 6 = 46.

PROG