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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
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
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 A347786 A036588
KEYWORD
hard,nonn
AUTHOR
Rick L. Shepherd, May 21 2008
STATUS
approved