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A109660 Numbers n such that the sum of the digits of n^phi(n) is divisible by n. 0
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; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..30.

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

Sequence in context: A294283 A294122 A211539 * A236544 A075855 A140189

Adjacent sequences:  A109657 A109658 A109659 * A109661 A109662 A109663

KEYWORD

base,nonn

AUTHOR

Ryan Propper, Aug 06 2005

EXTENSIONS

More terms from Emeric Deutsch, Feb 05 2006

STATUS

approved

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Last modified November 14 04:44 EST 2019. Contains 329108 sequences. (Running on oeis4.)