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A113826
Numbers n such that (n+1)^7 - n^7 is prime.
2
1, 3, 6, 7, 8, 9, 11, 16, 25, 32, 35, 38, 40, 48, 50, 54, 58, 65, 77, 78, 79, 87, 95, 97, 103, 112, 117, 119, 122, 134, 135, 141, 145, 155, 156, 159, 161, 172, 175, 193, 209, 218, 219, 220, 221, 223, 231, 233, 246, 280, 290, 296, 297, 304, 309, 310, 311, 322, 327
OFFSET
1,2
LINKS
MAPLE
L:= NULL: for x from 1 to 1000 do if isprime((x+1)^7 - x^7) then L:= L, x fi od: L;
MATHEMATICA
Flatten[Position[Partition[Range[400]^7, 2, 1], _?(PrimeQ[Last[#]- First[ #]]&), {1}, Heads->False]] (* Harvey P. Dale, Aug 20 2013 *)
Select[Range[0, 400], PrimeQ[(# + 1)^7 - #^7] &] (* Vincenzo Librandi, Apr 20 2014 *)
PROG
(Magma) [n: n in [0..350] | IsPrime((n+1)^7-n^7)]; // Vincenzo Librandi, Apr 20 2014
(PARI) is(n)=isprime((n+1)^7-n^7) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A299493 A047559 A288742 * A376588 A053030 A189822
KEYWORD
easy,nonn
AUTHOR
Robert Israel, Jan 24 2006
STATUS
approved