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A109662 Numbers n such that the sum of the digits of (n^n - n!) is divisible by n. 0
1, 2, 3, 9, 14, 15, 29, 33, 45, 81, 102, 105, 126, 142, 157, 288, 414, 1184, 2133, 10449, 16369, 17221, 46524, 214179, 216741 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

The quotients are: 0, 1, 1, 5, 5, 6, 7, 6, 8, 9, 9, 9, 9, 10, 10, 11, 12, 14, 15, 18, 19, 19, 21, 24, 24.

No more terms < 500000. [Lars Blomberg, Jul 05 2011]

EXAMPLE

The digits of 414^414 - 414! sum to 4968 and 4968 is divisible by 414, so 414 is in the sequence.

MATHEMATICA

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

CROSSREFS

Sequence in context: A048744 A101234 A057293 * A116222 A048038 A113501

Adjacent sequences:  A109659 A109660 A109661 * A109663 A109664 A109665

KEYWORD

base,more,nonn

AUTHOR

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

EXTENSIONS

Terms a(20)-a(25) from Lars Blomberg, Jul 05 2011.

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Last modified February 17 17:35 EST 2012. Contains 206061 sequences.