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A140669 Numbers n such that (n+1)^(n+1) - n^n is prime. 1
1, 2, 3, 6, 10, 16, 105, 119, 1906, 7917 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Terms found with PrimeForm. Primes corresponding to 16, 105 and 119 certified with Primo. 7917 corresponds to a 30870-digit probable prime.

LINKS

Table of n, a(n) for n=1..10.

Eric Weisstein's World of Mathematics, Integer Sequence Primes

Eric Weisstein's World of Mathematics, Power Difference Prime

EXAMPLE

17^17 - 16^16 = 808793517812627212561, which is prime, so 16 is a term.

MATHEMATICA

Select[Table[n, {n, 8000}], PrimeQ[(#+1)^(#+1)-#^#]&] (* Vladimir Joseph Stephan Orlovsky, Mar 03 2011*)

CROSSREFS

Cf. A134985. Equals A072164 - 1.

Sequence in context: A294444 A066895 A105075 * A001636 A036588 A334893

Adjacent sequences:  A140666 A140667 A140668 * A140670 A140671 A140672

KEYWORD

hard,nonn

AUTHOR

Rick L. Shepherd, May 21 2008

STATUS

approved

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Last modified April 10 08:09 EDT 2021. Contains 342845 sequences. (Running on oeis4.)