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.

Showing 1-4 of 4 results.

A079011 Least prime p introducing prime-difference pattern {d, 2*d}, where d = 2*n, i.e., {p, p+2*n, p+2*n+4*n} = {p, p+2*n, p+6*n} are consecutive primes.

Original entry on oeis.org

5, 397, 503, 1823, 1627, 8317, 5939, 94153, 69539, 83117, 444187, 177019, 428873, 1179649, 955511, 1625027, 2541289, 1290683, 19856363, 12183757, 5412091, 23374859, 27248701, 38235013, 21369059, 34718041, 84120737, 59859131, 125283913, 44155159, 70136597, 324954127
Offset: 1

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Author

Labos Elemer, Jan 21 2003

Keywords

Examples

			For n=3, d = 2*n = 6, d-pattern = {6, 12}, a(3) = 503, first corresponding prime triple is {503, 509, 521}.
		

Crossrefs

Programs

  • Mathematica
    d[x_] := Prime[x+1]-Prime[x]; t=Table[0, {70}]; Do[s=d[n]/2; If[(d[n+1]==4*s)&&(t[[s]]==0), t[[s]]=Prime[n]], {n, 2, 100000}]; t
  • PARI
    a(n) = my(p=5, q=3, r=2); until(r+2*n==q&&q+4*n==p, r=q; q=p; p=nextprime(p+1)); r; \\ Jinyuan Wang, Feb 10 2021

Extensions

Terms corrected and more terms from Jinyuan Wang, Feb 10 2021

A079013 Least prime p introducing prime-difference pattern {d, 2*d, 4*d, 8*d}, where d = 2*n, i.e., {p, p+2*n, p+6*n, p+14*n, p+30*n} are consecutive primes.

Original entry on oeis.org

2237, 1197739, 8052641, 18365693, 151738897, 196061237, 946120169, 15367934161, 36116700523, 49526343773
Offset: 1

Views

Author

Labos Elemer, Jan 21 2003

Keywords

Examples

			For n=4, d = 2*n = 8, d-pattern = {8, 16, 32, 64}, a(6)=18365693, first corresponding prime 5-tuplet is {18365693, 18365701, 18365717, 18365729, 18365793}.
		

Crossrefs

Extensions

a(8)-a(10) from Jinyuan Wang, Feb 11 2021

A079015 Primes introducing consecutive prime 6-tuple of primes or 5-tuple corresponding consecutive p-difference pattern as follows: {d, 2*d, 4*d, 8*d, 16*d}.

Original entry on oeis.org

6824897, 10132607, 12674657, 13699457, 14148047, 27353237, 43918997, 44152307, 50608007, 53944337, 60426257, 60825827, 61325057, 68721047, 68933717, 72069707, 78577817, 82108127, 82334297, 87020177, 88226777, 97013927, 102043757, 106053917, 114412937, 122271557
Offset: 1

Views

Author

Labos Elemer, Jan 22 2003

Keywords

Examples

			prime(45277466) = 884909087 is followed by {2, 4, 8, 16, 32, 10, 50, ...} difference pattern.
prime(9312431) = 166392559 initiates {4, 8, 16, 32, 64, 14, 30, ...} difference pattern of consecutive primes.
		

Crossrefs

Programs

  • Mathematica
    d[x_] := Prime[x+1]-Prime[x]; k=0; Do[s=d[n]; If[Equal[d[n+1], 2*s]&&Equal[d[n+2], 4*s]&&Equal[d[n+3], 8*s] &&Equal[d[n+4], 16*s], k=k+1; Print[{n, Prime[n]}]], {n, 1, 100000000}]
    (* or *)
    prmsUpTo[k_] :=
     First /@ Select[Partition[Prime@ Range[PrimePi[k]], 6, 1],
       Differences @# == {2, 4, 8, 16, 32} &]; prmsUpTo[10^9] (* Mikk Heidemaa, Apr 26 2024 *)

Extensions

More terms from Jinyuan Wang, Feb 10 2021

A079014 a(n) is the least prime initiating consecutive prime difference pattern consisting of n increasing consecutive powers of 2 started with 2.

Original entry on oeis.org

2, 3, 5, 1997, 2237, 6824897, 1356705137, 3637803390827
Offset: 0

Views

Author

Labos Elemer, Jan 21 2003

Keywords

Examples

			n=6: a(6) = p(67928439) = 1356705137 because {p, p+2, p+2+4, p+2+4+8, p+2+...+16, p+2+...+32, p+2+...+64} = {p, p+2, p+6, p+14, p+30, p+62, p+126} are consecutive primes.
		

Crossrefs

Extensions

Missing a(1)=3 inserted by Sean A. Irvine, Jul 27 2025
a(7) (from A090807) added by Pontus von Brömssen, Aug 27 2025
Showing 1-4 of 4 results.