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.

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A022012 Initial members of prime octuplets (p, p+2, p+6, p+12, p+14, p+20, p+24, p+26).

Original entry on oeis.org

17, 1277, 113147, 2580647, 20737877, 58208387, 73373537, 76170527, 100658627, 134764997, 137943347, 165531257, 171958667, 224008217, 252277007, 294536147, 309740987, 311725847, 364154027, 408936947, 515447747, 521481197, 528272177, 619010297, 626927447, 682809977
Offset: 1

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Keywords

Comments

All terms are congruent to 17 (modulo 30). - Matt C. Anderson, May 26 2015

Crossrefs

A065706 is the union of A022011, A022012 and A022013.
A346997(n) = a(10^n).

Programs

  • Magma
    [p: p in PrimesUpTo(4*10^8) | forall{p+r: r in [2,6,12,14,20,24,26] | IsPrime(p+r)}]; // Vincenzo Librandi, Oct 01 2015
    
  • Mathematica
    Select[Prime[Range[2 10^9]], Union[PrimeQ[# + {2, 6, 12, 14, 20, 24, 26}]] == {True} &] (* Vincenzo Librandi, Oct 01 2015 *)
  • PARI
    forprime(p=2, 10^30, if (isprime(p+2) && isprime(p+6) && isprime(p+12) && isprime(p+14) && isprime(p+20) && isprime(p+24) && isprime(p+26), print1(p", "))) \\ Altug Alkan, Oct 01 2015
  • Perl
    use ntheory ":all"; say for sieve_prime_cluster(1,1e10, 2,6,12,14,20,24,26); # Dana Jacobsen, Sep 30 2015
    

A347850 Record gaps between prime octuplets of the form p + {0, 2, 6, 12, 14, 20, 24, 26} (initial members are A022012), divided by 30.

Original entry on oeis.org

42, 3729, 82250, 605241, 1249017, 1734985, 1747606, 3550360, 9578800, 10562911, 12208504, 24101070, 26510262, 38121281, 38588851, 47884158, 50246371, 56392908, 59827439, 66233760, 114058040, 120197366, 141646351, 141808504, 153247005, 168751151, 235079194, 244505074
Offset: 1

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Author

Hugo Pfoertner and Norman Luhn, Sep 16 2021

Keywords

Examples

			a(1) = (A022012(2) - A022012(1))/30 = (1277 - 17)/30 = 42; 17 = A347851(1).
a(5) = (A022012(13) - A022012(12))/30 = (171958667 - 165531257)/30 = 214247, exceeding all previous differences; 1655531257 = A347851(5).
		

Crossrefs

The primes at the lower end of the record gaps are given in A347851.
Showing 1-2 of 2 results.