cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A187058 Primes p such that the polynomial x^2 + x + p generates only primes for x = 1..5.

Original entry on oeis.org

11, 17, 41, 1277, 1607, 3527, 13901, 21557, 26681, 28277, 31247, 33617, 55661, 68897, 97367, 113147, 128981, 166841, 195731, 221717, 347981, 348431, 354371, 416387, 421697, 506327, 548831, 566537, 665111, 844427, 929057, 954257
Offset: 1

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Author

Jonathan Vos Post, Mar 03 2011

Keywords

Comments

From Weber, p. 15.
This sequence is infinite, assuming Dickson's conjecture.
All terms = {11, 17} mod 30. - Zak Seidov, May 07 2011

Examples

			a(2) = 17 because x^2 + x + 17 generates 0^2 + 0 + 17 = 17; 1^2 + 1 + 17 = 19; 2^2 + 2 + 17 = 23; 3^2 + 3 + 17 = 29; 4^2 + 4 + 17 = 37; and 5^2 + 5 + 17 = 47, all primes.
		

Crossrefs

Programs

  • Mathematica
    okQ[n_] := And @@ PrimeQ[Table[i^2 + i + n, {i, 0, 5}]]; Select[Range[10000], okQ] (* T. D. Noe, Mar 03 2011 *)
    Select[Prime[Range[76000]],AllTrue[#+{2,6,12,20,30},PrimeQ]&] (* Harvey P. Dale, Apr 12 2025 *)
  • PARI
    forprime(p=9,1e6,if((p%30==11 || p%30==17) && isprime(p+2) && isprime(p+6) && isprime(p+12) && isprime(p+20) && isprime(p+30), print1(p", "))) \\ Charles R Greathouse IV, May 08 2011