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 1-3 of 3 results.

A139533 Numbers k such that numbers 24*k + 11 and 24*k + 13 are twin primes.

Original entry on oeis.org

0, 2, 4, 7, 9, 14, 17, 27, 34, 42, 45, 59, 60, 67, 69, 74, 80, 84, 94, 97, 135, 137, 140, 144, 147, 160, 167, 170, 177, 189, 199, 205, 212, 235, 244, 255, 262, 277, 282, 284, 289, 300, 304, 305, 314, 342, 345, 349, 359, 367, 375, 392, 419, 420, 422, 430, 434, 437
Offset: 1

Views

Author

Artur Jasinski, Apr 25 2008

Keywords

Links

Crossrefs

Numbers k such that:
24*k - 1 and 24*k + 1 are twin primes, see A137920.
24*k + 5 and 24*k + 7 are twin primes, see A139404.
24*k + 17 and 24*k + 19 are twin primes, see A139534.

Programs

  • Magma
    [k:k in [0..450]|IsPrime(24*k + 11) and IsPrime(24*k + 13)]; // Marius A. Burtea, Dec 31 2019
  • Mathematica
    a = {}; Do[If[PrimeQ[24 n + 11] && PrimeQ[24 n + 13], AppendTo[a, n]], {n, 0, 2000}]; a

A139534 Numbers k such that numbers 24*k + 17 and 24*k + 19 are twin primes.

Original entry on oeis.org

0, 1, 5, 11, 21, 23, 25, 26, 33, 35, 36, 43, 53, 61, 70, 71, 86, 88, 110, 113, 116, 123, 135, 138, 163, 166, 168, 175, 176, 180, 186, 193, 196, 208, 225, 226, 235, 243, 253, 268, 273, 278, 281, 310, 333, 355, 373, 376, 386, 410, 413, 435, 438, 453, 455, 460, 478
Offset: 1

Views

Author

Artur Jasinski, Apr 25 2008

Keywords

Links

Crossrefs

Cf. A137920, A139404, A139533.

Programs

  • Magma
    [k:k in [0..500]|IsPrime(24*k + 17) and IsPrime(24*k + 19)]; // Marius A. Burtea, Dec 31 2019
  • Mathematica
    a = {}; Do[If[PrimeQ[24 n + 17] && PrimeQ[24 n + 19], AppendTo[a, n]], {n, 0, 2000}]; a

A137919 (Nextprime(24n)-previousprime(24n))/2.

Original entry on oeis.org

3, 3, 1, 4, 7, 5, 3, 1, 6, 1, 3, 5, 1, 3, 4, 3, 4, 1, 4, 4, 3, 9, 5, 3, 1, 6, 3, 6, 5, 4, 4, 4, 5, 5, 7, 7, 10, 4, 4, 7, 4, 6, 1, 5, 9, 3, 3, 1, 5, 4, 3, 6, 9, 3, 1, 17, 3, 9, 7, 4, 6, 1, 6, 6, 4, 7, 1, 5, 10, 12, 5, 5, 3, 9, 6, 4, 7, 1, 6, 9, 8, 11, 3, 3, 7, 3, 1, 1, 3, 4, 12, 3, 8, 8, 4, 6, 11, 3, 3, 6, 7, 6
Offset: 1

Views

Author

Zak Seidov, Feb 23 2008

Keywords

Comments

a(n)=1 if 24n -/+ 1 are twin primes.
Corresponding n's are in A137920.

Crossrefs

Cf. A124519, A135023, A135368, A137876, A137877, A137920.

Programs

  • Mathematica
    Table[(NextPrime[24n]-NextPrime[24n,-1])/2,{n,110}] (* Harvey P. Dale, Apr 15 2015 *)
  • PARI
    a(n) = (nextprime(24*n) - precprime(24*n))/2; \\ Michel Marcus, Oct 13 2013
Showing 1-3 of 3 results.

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