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.

A078963 Primes p such that the differences between the 5 consecutive primes starting with p are (6,4,6,2).

Original entry on oeis.org

3313, 4993, 5851, 9613, 17971, 23011, 32353, 36913, 45121, 51421, 53881, 54403, 59611, 76243, 90001, 91951, 127591, 130633, 131431, 134353, 140401, 142963, 174061, 229753, 246913, 267661, 303361, 311551, 321313, 340111, 386143, 435553, 465061, 514513, 532993, 618571
Offset: 1

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Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+6, p+10, p+16 and p+18 are consecutive primes.

Examples

			23011 is in the sequence since 23011, 23017 = 23011 + 6, 23021 = 23011 + 10, 23027 = 23011 + 16 and 23029 = 23011 + 18 are consecutive primes.
		

Crossrefs

Subsequence of A078856. - R. J. Mathar, May 06 2017

Programs

  • Maple
    L:= [2,3,5,7,11]:
    count:= 0: Res:= NULL:
    while count < 50 do
      L:= [op(L[2..5]),nextprime(L[5])];
      if L - [L[1]$5] = [0,6,10,16,18] then
        count:= count+1;
        Res:= Res, L[1];
      fi
    od:
    Res; # Robert Israel, Jun 04 2018
  • Mathematica
    Transpose[Select[Partition[Prime[Range[50000]],5,1],Differences[#]=={6,4,6,2}&]][[1]]  (* Harvey P. Dale, Mar 04 2011 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 6 && p3 - p2 == 4 && p4 - p3 == 6 && p5 - p4 == 2, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 22 2025

Formula

From Amiram Eldar, Feb 22 2025: (Start)
a(n) == 1 (mod 6).
a(n) == 1 or 13 (mod 30). (End)

Extensions

Edited by Dean Hickerson, Dec 20 2002