A271143 Numbers k such that 42*k^3 + 270*k^2 - 26436*k + 250703 is prime.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 43, 44, 48, 51, 54, 55, 56, 58, 61, 62, 63, 64, 65, 66, 67, 69, 71, 76, 78, 79, 84, 87, 88, 89, 90, 92

Offset: 1

Author

Robert Price, Apr 23 2016

Keywords

• nonn

Comments

40 is the first value not in the sequence.

Examples

			4 is in this sequence since 42*4^3 + 270*4^2 - 26436*4 + 250703 = 151967, which is prime.
		

Links

• Robert Price, Table of n, a(n) for n = 1..3092
• Eric Weisstein's World of Mathematics, Prime-Generating Polynomials

Crossrefs

Cf. A050265-A050268, A005846, A007641, A007635, A048988, A256585, A271980, A272074, A272075, A272160, A271144.

Programs

Mathematica

Select[Range[0, 100], PrimeQ[42#^3 + 270#^2 - 26436# + 250703] &]

PARI

is(n)=isprime(42*n^3+270*n^2-26436*n+250703) \\ Charles R Greathouse IV, Feb 17 2017