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A266970 Primes of the form x^3 + x*y + y^3 where x and y are positive integers. 1
3, 11, 31, 41, 103, 131, 167, 223, 503, 521, 563, 601, 677, 739, 829, 911, 1361, 1439, 1511, 1613, 1741, 1913, 1931, 2441, 2939, 3191, 3391, 3413, 3499, 3671, 3823, 4007, 4229, 4871, 4931, 4969, 5231, 5851, 6047, 6301, 6329, 7079, 7331, 7523, 7759, 8087, 8263, 8543, 9281, 9283 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
11 is a term because 2^3 + 2*1 + 1^3 = 11 is prime.
31 is a term because 3^3 + 3*1 + 1^3 = 31 is prime.
41 is a term because 3^3 + 3*2 + 2^3 = 41 is prime.
MATHEMATICA
nn = 10000; lim = Floor[nn^(1/3)]; Union[Reap[Do[p = a^3 + a*b + b^3; If[p <= nn && PrimeQ[p], Sow[p]], {a, lim}, {b, a}]][[2, 1]]] (* Wesley Ivan Hurt, Jan 07 2016 after T. D. Noe *)
lim=100; Select[Union[Flatten[Table[x^3 + x y + y^3, {x, 0, lim}, {y, 0, lim}]]], #>0 && #<lim^2 && PrimeQ[#] &] (* Vincenzo Librandi, Jan 08 2016 *)
CROSSREFS
Sequence in context: A003523 A018781 A119215 * A057172 A277167 A277049
KEYWORD
nonn
AUTHOR
Altug Alkan, Jan 07 2016
STATUS
approved

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Last modified February 25 13:12 EST 2024. Contains 370330 sequences. (Running on oeis4.)