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.

Showing 1-2 of 2 results.

A155736 Numbers n such that 4*n^2+2*n-1 is a prime.

Original entry on oeis.org

1, 2, 3, 4, 5, 8, 10, 12, 13, 14, 15, 19, 22, 23, 24, 25, 27, 28, 30, 32, 33, 34, 35, 38, 43, 47, 48, 50, 57, 60, 63, 65, 67, 69, 70, 72, 74, 77, 79, 80, 82, 87, 88, 90, 92, 93, 94, 98, 103, 109, 110, 115, 118, 120, 122, 123, 124, 129, 132, 134, 144, 145, 147, 148, 149
Offset: 1

Views

Author

Vincenzo Librandi, Jan 26 2009

Keywords

Links

Crossrefs

Cf. A155737, A155738.

Programs

  • Magma
    [n: n in [0..150] | IsPrime(4*n^2+2*n-1)]; // Vincenzo Librandi, Sep 24 2012
  • Mathematica
    Select[Range[0, 200], PrimeQ[4#^2+2#-1]&] (* Vincenzo Librandi, Sep 24 2012 *)

Extensions

Edited by N. J. A. Sloane, Jun 25 2010

A155738 Primes p such that 4*p^2+2*p-1 is also prime.

Original entry on oeis.org

2, 3, 5, 13, 19, 23, 43, 47, 67, 79, 103, 109, 149, 157, 179, 193, 239, 353, 373, 397, 419, 487, 499, 503, 523, 547, 563, 569, 587, 619, 677, 683, 787, 797, 839, 853, 863, 929, 1013, 1093, 1193, 1229, 1289, 1303, 1319, 1423, 1433, 1499, 1553, 1619, 1669, 1733
Offset: 1

Views

Author

Vincenzo Librandi, Jan 26 2009

Keywords

Links

Crossrefs

Cf. A155736, A155737.

Programs

  • Magma
    [p: p in PrimesUpTo(1800)| IsPrime(4*p^2 + 2*p - 1)]; // Vincenzo Librandi, Oct 30 2012
  • Mathematica
    Select[Prime[Range[400]],PrimeQ[4#^2+2#-1]&]  (* Harvey P. Dale, Mar 22 2011 *)

Formula

A155736 INTERSECT A000040. [R. J. Mathar, Jan 05 2011]
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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