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A093666 Numbers n such that n | 3^n^2 + 1. 1
1, 2, 82, 3362, 137842, 188354, 5651522, 7722514, 13232914, 231712402, 316623074, 432649138, 542549474, 1196468642, 2650762258, 9500208482, 12981546034, 17738614658, 22244528434, 30396003458, 49055214322, 108681252578, 389508547762, 532243387394, 727283200978, 912025665794, 993795069986 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If n is a term and p is its odd prime divisor, then p*n is also a term. In particular, the sequence contains 2*41^k and 2*41*2297^k for all k>=1.

LINKS

Table of n, a(n) for n=1..27.

MATHEMATICA

Select[ Range[ 250000000], PowerMod[3, #^2, # ] +1 == # & ]

CROSSREFS

Cf. A015949, A092408, A093546.

Sequence in context: A307583 A061994 A197641 * A246002 A063270 A087617

Adjacent sequences:  A093663 A093664 A093665 * A093667 A093668 A093669

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Apr 02 2004

EXTENSIONS

Terms a(11) onward from Max Alekseyev, Feb 13 2012

STATUS

approved

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Last modified November 20 02:34 EST 2019. Contains 329323 sequences. (Running on oeis4.)