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A100408 Numbers n such that n^n-2 is prime. 4
2, 7, 19, 21, 25, 49, 51, 1071 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for the first term all terms are odd.

Numbers n such that n^n+7 is prime gives the (as yet) too-short sequence 2,4,6,32,...

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

51 is in the sequence because 51^51-2 is prime. 1071^1071-2 is a probable prime.

MATHEMATICA

Do[If[PrimeQ[n^n-2], Print[n]], {n, 1111}]

CROSSREFS

Cf. A100407.

Sequence in context: A185308 A002214 A218684 * A259370 A103034 A038952

Adjacent sequences:  A100405 A100406 A100407 * A100409 A100410 A100411

KEYWORD

more,nonn

AUTHOR

Farideh Firoozbakht, Nov 19 2004

STATUS

approved

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Last modified December 3 04:39 EST 2016. Contains 278698 sequences.