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A058046 Numbers n such that 5^n - n is prime. 0
2, 6, 12, 362, 884, 9722 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Farideh Firoozbakht reports that the only known prime of the form 5^n + n occurs when n = 7954 and that there are no others up to 20200. Oct 11 2003.

MATHEMATICA

Do[ If[ PrimeQ[ 5^n - n ], Print[ n ] ], {n, 1, 13400} ]

CROSSREFS

Sequence in context: A179201 A105122 A132076 * A192321 A074180 A126293

Adjacent sequences:  A058043 A058044 A058045 * A058047 A058048 A058049

KEYWORD

nonn

AUTHOR

Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 17 2000

EXTENSIONS

The sixth term was found by Farideh Firoozbakht (f.firoozbakht(AT)sci.ui.ac.ir), who reports that there are no others up to 13400, Oct 11 2003

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Last modified February 15 10:06 EST 2012. Contains 205763 sequences.