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.

A118072 Primes which are the sum of a twin prime pair - 1.

Original entry on oeis.org

7, 11, 23, 59, 83, 359, 383, 479, 563, 839, 863, 1283, 1319, 1619, 2039, 2063, 2099, 2459, 2579, 2903, 2963, 3863, 4259, 4283, 4679, 5099, 5939, 6599, 6659, 6719, 6779, 7079, 7643, 7703, 8039, 8543, 8963, 10463, 10559, 10883, 11003, 11279, 11483, 11699, 12263
Offset: 1

Views

Author

Jonathan Vos Post, May 11 2006

Keywords

Comments

Dickson's conjecture implies this sequence is infinite. - Charles R Greathouse IV, Apr 18 2013

Examples

			a(1) = 7 = 3 + 5 - 1 where (3,5) is a twin prime pair.
a(2) = 11 = 5 + 7 - 1 where (5,7) is a twin prime pair.
		

Crossrefs

Programs

  • Magma
    [p: p in PrimesUpTo(13000)|IsPrime((p-1) div 2) and IsPrime((p+3) div 2)]; // Marius A. Burtea, Jan 01 2020
  • Mathematica
    Select[(Total[#]-1)&/@Select[Partition[Prime[Range[500]],2,1], Last[#]- First[#]== 2&],PrimeQ]  (* Harvey P. Dale, Apr 04 2011 *)
  • PARI
    is(p)=isprime((p-1)\2)&&isprime((p+3)\2)&&isprime(p) \\ Charles R Greathouse IV, Apr 18 2013
    

Formula

{A001359(k) + A006512(k) - 1} INTERSECT {A000040}. {A054735(k) - 1} INTERSECT {A000040}. {2*A001359(k) + 1} INTERSECT {A000040}.

Extensions

More terms from Harvey P. Dale, Apr 04 2011
More terms from Amiram Eldar, Jan 01 2020