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 A265670 Numbers n such that n^5 + n^4 + n^3 + n^2 + n - 1 is prime. 0

%I

%S 2,8,10,12,16,18,22,24,28,32,42,50,60,68,70,78,88,104,108,118,132,138,

%T 206,238,240,242,270,282,300,306,312,318,338,372,376,382,390,394,398,

%U 418,440,452,464,512,522,532,534,548,566,586,594,626,630,636,640,650

%N Numbers n such that n^5 + n^4 + n^3 + n^2 + n - 1 is prime.

%C All terms are even. - _Altug Alkan_, Dec 13 2015

%e 2 is in the sequence because 2^5 + 2^4 + 2^3 + 2^2 + 2 - 1 = 61 is prime.

%t Select[Range[700], PrimeQ[Total[#^Range[1, 5, 1]] - 1] &]

%o (MAGMA) [n: n in [0..700] | IsPrime(s) where s is n^5+n^4+n^3+n^2+n-1];

%o (PARI) print1(2, ", "); forcomposite(n=1, 1e4, if(ispseudoprime(n^5 + n^4 + n^3 + n^2 + n - 1), print1(n, ", "))) \\ _Altug Alkan_, Dec 13 2015

%Y Cf. A045546, A100331, A125964, A182424.

%K nonn,easy

%O 1,1

%A _Vincenzo Librandi_, Dec 13 2015

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Last modified April 14 01:17 EDT 2021. Contains 342941 sequences. (Running on oeis4.)