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A084914 Numbers k such that k^k*k! - 1 is prime. 1
2, 4, 30, 94, 113, 162, 296, 3243 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(1)-a(8) have been proved to correspond to primes. No other terms less than 10000. - Robert Price, May 19 2012

LINKS

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

EXAMPLE

4 is in the sequence because 4!*4^4 - 1 = 6143 is prime.

MATHEMATICA

Do[If[PrimeQ[n^n*n!-1], Print[n]], {n, 700}]

CROSSREFS

Cf. A002981, A002982.

Sequence in context: A232173 A067195 A080230 * A058779 A230777 A241542

Adjacent sequences:  A084911 A084912 A084913 * A084915 A084916 A084917

KEYWORD

more,hard,nonn

AUTHOR

Farideh Firoozbakht, Jul 14 2003

EXTENSIONS

a(8) = 3243 from Robert Price, May 19 2012

STATUS

approved

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Last modified January 16 09:13 EST 2021. Contains 340204 sequences. (Running on oeis4.)