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A056739 Numbers n such that n | 10^n + 9^n + 8^n + 7^n + 6^n + 5^n + 4^n + 3^n + 2^n + 1^n. 0
1, 5, 11, 25, 55, 121, 125, 275, 365, 605, 625, 925, 1331, 1375, 2365, 3025, 3125, 6655, 6875, 14641, 15125, 15625, 22625, 27565, 32125, 33275, 34375, 73205, 75625, 78125, 123365, 161051, 166375, 171875, 366025, 378125, 390625, 541717, 660605 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Contains A003598. In general n=p^iq^i => n|Sum[k=1..2p, k^n], where p, q=2p+1 prime (see Meyer ref).

LINKS

C. Meyer, On a conjecture arising from the OEIS

MATHEMATICA

Do[ If[ Mod[ PowerMod[ 10, n, n ] + PowerMod[ 9, n, n ] + PowerMod[ 8, n, n ] + PowerMod[ 7, n, n ] + PowerMod[ 6, n, n ] + PowerMod[ 5, n, n ] + PowerMod[ 4, n, n ] + PowerMod[ 3, n, n ] + PowerMod[ 2, n, n ] + 1, n ] == 0, Print[ n ] ], {n, 1, 10^6} ]

CROSSREFS

Cf. A001557.

Sequence in context: A059358 A167238 A084640 * A003598 A014858 A018368

Adjacent sequences:  A056736 A056737 A056738 * A056740 A056741 A056742

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Aug 25 2000

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Last modified February 16 16:00 EST 2012. Contains 205938 sequences.