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A125885
Numbers k for which k^7+k^6-1 is prime.
15
2, 4, 12, 17, 27, 39, 45, 46, 72, 94, 105, 106, 122, 126, 147, 149, 151, 156, 160, 161, 166, 169, 171, 172, 192, 194, 204, 205, 209, 230, 235, 242, 252, 260, 264, 266, 276, 280, 285, 306, 309, 319, 330, 335, 357, 371, 387, 400, 402, 411, 422, 439, 442, 451, 459
OFFSET
1,1
LINKS
MATHEMATICA
Do[If[PrimeQ[x^7 + x^6 - 1], Print[x]], {x, 1, 200}]
PROG
(PARI) is(n)=isprime(n^7+n^6-1) \\ Charles R Greathouse IV, May 15 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Dec 14 2006
EXTENSIONS
More terms from Amiram Eldar, Mar 18 2020
STATUS
approved