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.

A163385 Primes p such that 3(p-3)-1 and 3(p-3)+1 are twin primes.

Original entry on oeis.org

5, 7, 13, 17, 23, 37, 53, 67, 79, 83, 97, 107, 157, 193, 223, 277, 347, 353, 367, 433, 443, 479, 487, 499, 569, 577, 599, 647, 653, 773, 797, 853, 907, 937, 1087, 1103, 1123, 1259, 1277, 1367, 1409, 1423, 1427, 1549, 1553, 1747, 1889, 2069, 2153, 2237, 2267
Offset: 1

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Comments

In other words, primes p such that 3*(p-3) is a term of A014574. - Omar E. Pol, Aug 05 2009

Examples

			3*(5-3) = 6, 3*(7-3) = 12, 3*(13-3) = 30, ...
		

Crossrefs

Cf. A163386, A163387, A163388. - Omar E. Pol, Aug 05 2009

Programs

  • Maple
    select(p -> isprime(p) and isprime(3*p-10) and isprime(3*p-8), [seq(i,i=3..10000,2)]); # Robert Israel, Nov 13 2016
  • Mathematica
    f1[n_]:=If[PrimeQ[n-1]&&PrimeQ[n+1],True,False]; f2[n_]:=If[f1[n]&&PrimeQ[n/3+3],True,False]; lst={};Do[If[f2[n],AppendTo[lst,n/3+3]],{n,8!}];lst
    Select[Prime[Range[400]],AllTrue[3(#-3)+{1,-1},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 16 2017 *)

Extensions

Definition clarified and edited by Omar E. Pol, Aug 05 2009