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.

A213739 Numbers n such that n and n^2 are sums of two successive primes.

Original entry on oeis.org

12, 24, 42, 84, 90, 120, 204, 240, 372, 410, 456, 600, 630, 740, 762, 852, 882, 978, 1088, 1140, 1148, 1272, 1460, 1518, 1584, 1620, 1656, 1758, 1770, 1878, 1900, 1960, 2052, 2316, 2562, 2688, 2886, 2992, 3570, 3634, 3678, 3738, 3750, 3924, 4170, 4314, 4906
Offset: 1

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Author

Zak Seidov, Jun 19 2012

Keywords

Comments

First terms not multiple of 6: 410, 740, 1088, 1148, 1460, 1900, 1960.

Examples

			12=5+7, 144=71+73;
24=11+13, 576=283+293;
42=19+23, 1764=881+883.
		

Crossrefs

Intersection of A001043 and A074924.

Programs

  • Mathematica
    Reap[ Do[ If[ (p=NextPrime[n/2, -1]; p+NextPrime[p] == n) && (q=NextPrime[n^2/2, -1]; q+NextPrime[q] == n^2) , Sow[n]], {n, 2, 5000, 2}]][[2, 1]] (* Jean-François Alcover, Jul 17 2012 *)
  • PARI
    p=2;forprime(q=3,1e3,n=p+q;if(precprime(n^2/2)+nextprime((n^2+1)/2)==n^2,print1(n", "));p=q) \\ Charles R Greathouse IV, Jun 21 2012