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A265670 Numbers n such that n^5 + n^4 + n^3 + n^2 + n - 1 is prime. 0
2, 8, 10, 12, 16, 18, 22, 24, 28, 32, 42, 50, 60, 68, 70, 78, 88, 104, 108, 118, 132, 138, 206, 238, 240, 242, 270, 282, 300, 306, 312, 318, 338, 372, 376, 382, 390, 394, 398, 418, 440, 452, 464, 512, 522, 532, 534, 548, 566, 586, 594, 626, 630, 636, 640, 650 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are even. - Altug Alkan, Dec 13 2015

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

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

MATHEMATICA

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

PROG

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

(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

CROSSREFS

Cf. A045546, A100331, A125964, A182424.

Sequence in context: A081693 A022298 A229090 * A297999 A287088 A296342

Adjacent sequences:  A265667 A265668 A265669 * A265671 A265672 A265673

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 13 2015

STATUS

approved

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Last modified October 18 18:58 EDT 2018. Contains 316323 sequences. (Running on oeis4.)