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A109660 Numbers n such that the sum of the digits of n^phi(n) is divisible by n. +0
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1, 2, 3, 7, 9, 15, 18, 27, 52, 72, 261, 360, 400, 3932, 4418, 7046, 7938, 8888, 9162, 9363, 9606, 9738, 10083, 10809, 11970, 13958, 23571, 28384, 42159, 51515 (list; graph; listen)
OFFSET

1,2

EXAMPLE

The digits of 8888^phi(8888) sum to 71104 and 71104 is divisible by 8888, so 8888 is in the sequence.

MATHEMATICA

Do[s = n^EulerPhi[n]; k = Plus @@ IntegerDigits[s]; If[Mod[k, n] == 0, Print[n]], {n, 1, 10000}]

CROSSREFS

Adjacent sequences: A109657 A109658 A109659 this_sequence A109661 A109662 A109663

Sequence in context: A014837 A019312 A135369 this_sequence A075855 A140189 A165803

KEYWORD

base,nonn

AUTHOR

Ryan Propper (rpropper(AT)stanford.edu), Aug 06 2005

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Feb 05 2006

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Last modified November 8 20:39 EST 2009. Contains 166234 sequences.


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