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 A317979 Numbers k such that k^4 + k^3 + k^2 + 1 is prime. 1
 2, 4, 6, 8, 14, 22, 26, 32, 36, 54, 82, 96, 98, 108, 116, 120, 124, 132, 144, 152, 162, 164, 166, 182, 226, 240, 244, 246, 252, 254, 264, 266, 274, 276, 312, 314, 322, 328, 330, 352, 364, 368, 372, 382, 406, 410, 420, 422, 428, 430, 432, 438, 456 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The numbers in the sequence are all even numbers. For k = 11*m - 4, (k^4 + k^3 + k^2 + 1)/11 is an integer, so there is no number of the form k = 11*m - 4 in the sequence. LINKS Daniel Starodubtsev, Table of n, a(n) for n = 1..10000 EXAMPLE 2^4 + 2^3 + 2^2 + 1 = 29 is prime, so 2 is in the sequence. MATHEMATICA Select[Range[0, 1000], PrimeQ[#^4 + #^3 + #^2 + 1] &] PROG (PARI) for(n=1, 1000, if(ispseudoprime(n^4 + n^3 + n^2 + 1), print1(n, ", "))) (MAGMA) [n: n in [0..700] |IsPrime(n^4 + n^3 + n^2 + 1)]; // Vincenzo Librandi, Sep 08 2018 CROSSREFS Cf. A005574, A119863. Sequence in context: A156097 A288793 A039597 * A167229 A192333 A068902 Adjacent sequences:  A317976 A317977 A317978 * A317980 A317981 A317982 KEYWORD nonn AUTHOR Jinyuan Wang, Aug 12 2018 STATUS approved

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Last modified May 20 01:04 EDT 2022. Contains 353847 sequences. (Running on oeis4.)