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.

A095969 If p(k) is the k-th prime, then the n-th set of 2 consecutive cousin prime pairs starts at p(a(n)).

Original entry on oeis.org

4, 6, 12, 25, 27, 29, 48, 63, 88, 93, 134, 147, 149, 151, 153, 181, 211, 224, 235, 247, 249, 285, 301, 389, 433, 483, 612, 642, 694, 742, 877, 975, 994, 1037, 1039, 1080, 1094, 1153, 1276, 1278, 1301, 1380, 1395, 1439, 1474, 1563, 1580, 1617, 1638, 1688
Offset: 1

Views

Author

Ray G. Opao, Jul 15 2004

Keywords

Examples

			a(2)=6: p(6)=13 and p(7)=17, the first cousin prime pair, p(8)=19 and p(9)=23, the second cousin prime pair.
		

Programs

  • Magma
    [n: n in [1..2000] | NthPrime(n+1)-NthPrime(n) eq 4 and  NthPrime(n+3)-NthPrime(n+2) eq 4]; // Vincenzo Librandi, Jul 03 2015
  • Mathematica
    n=0 Do[If[Prime[k + 1] - Prime[k]==4&&Prime[k + 3] - Prime[k + 2]==4, n = n + 1; Print[n, " ", k]], {k, 1, 1700}] (* Vincenzo Librandi, Jul 03 2015 *)