

A108860


Numbers n such that n divides the sum of the digits of (2n)^n.


0



1, 3, 9, 12, 16, 18, 22, 27, 29, 33, 48, 54, 80, 127, 133, 149, 171, 335, 888, 1038, 1137, 1435, 1465, 1647, 13921, 14256, 22467, 22872, 23514, 23709, 39564, 108708, 108777, 109308, 230115
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OFFSET

1,2


COMMENTS

The quotients are: 2, 3, 7, 6, 7, 7, 7, 8, 8, 9, 9, 9, 5, 11, 11, 11, 11, 8, 15, 15, 15, 11, 11, 16, 20, 20, 21, 21, 21, 21, 22, 24, 24, 24, 21.


LINKS

Table of n, a(n) for n=1..35.


EXAMPLE

888 is a term because the sum of the digits of (2*888)^888, 13320, is divisible by 888.


MATHEMATICA

Do[If[Mod[Plus @@ IntegerDigits[(2*n)^n], n] == 0, Print[n]], {n, 1, 10000}]


PROG

(Python)
A108860_list = [n for n in range(1, 1000) if not sum(int(d) for d in str((2*n)**n)) % n] # Chai Wah Wu, Mar 15 2018


CROSSREFS

Sequence in context: A244147 A103531 A333441 * A006499 A310320 A274676
Adjacent sequences: A108857 A108858 A108859 * A108861 A108862 A108863


KEYWORD

base,hard,more,nonn


AUTHOR

Ryan Propper, Jul 11 2005


EXTENSIONS

Two additional terms from Harvey P. Dale, Nov 24 2010
a(27)a(35) from Lars Blomberg, Jul 02 2011


STATUS

approved



