A057257 - OEIS

A057257

Numbers n such that n | 12^n + 11^n + 10^n + 9^n + 8^n + 7^n.

1, 3, 9, 19, 27, 33, 57, 81, 171, 207, 243, 253, 361, 513, 729, 1083, 1539, 1791, 1809, 2187, 2673, 3249, 3699, 4617, 5643, 6561, 6859, 8303, 9747, 10449, 11601, 11913, 13851, 19683, 20493, 20577, 29241, 41193, 41553, 43263, 46569, 50301, 59049

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..43.

MATHEMATICA

Select[ Range[ 10^6 ], Mod[ PowerMod[ 12, #, # ] + PowerMod[ 11, #, # ] + PowerMod[ 10, #, # ] + PowerMod[ 9, #, # ] + PowerMod[ 8, #, # ] + PowerMod[ 7, #, # ], # ] == 0 & ]

Select[Range[60000], Divisible[Total[Table[PowerMod[i, n, n], {i, 7, 12}]], n]/.n->#&] (* Harvey P. Dale, Jun 23 2011 *)

PROG

(PARI) isA057257(n)=!sum(i=7, 12, Mod(i, n)^n) \\ Charles R Greathouse IV, Jun 24 2011

CROSSREFS

Sequence in context: A032670 A068677 A069832 * A029464 A029479 A215803

Adjacent sequences: A057254 A057255 A057256 * A057258 A057259 A057260

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Sep 21 2000

STATUS

approved