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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A078853 Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d = 2, 4 or 6) and forming d-pattern=[6,2,4]; short d-string notation of pattern = [624].

Original entry on oeis.org

1601, 3911, 5471, 8081, 12101, 12911, 13751, 14621, 17021, 32051, 38321, 40841, 43391, 58901, 65831, 67421, 67751, 68891, 69821, 72161, 80141, 89591, 90011, 90191, 97571, 100511, 102191, 111821, 112241, 122021, 125921, 129281, 129581
Offset: 1

Views

Author

Labos Elemer, Dec 11 2002

Keywords

Comments

All terms are == 11 (mod 30). Is 180 the minimal first difference? - Zak Seidov, Jun 27 2015
Subsequence of A049438. - R. J. Mathar, May 06 2017

Examples

			p=1601, 1601+6=1607, 1601+6+2=1609, 1601+6+2+4=1613 are consecutive primes.
		

Crossrefs

Cf. analogous prime quadruple sequences with various possible {2, 4, 6}-difference-patterns in brackets: A007530[242], A078847[246], A078848[264], A078849[266], A052378[424], A078850[426], A078851[462], A078852[466], this sequence[624], A078854[626], A078855[642], A078856[646], A078857[662], A078858[664], A033451[666].

Programs

  • Mathematica
    Transpose[Select[Partition[Prime[Range[13000]], 4, 1], Differences[#]=={6, 2, 4} &]][[1]] (* Vincenzo Librandi, Jun 27 2015 *)

Formula

Primes p = p(i) such that p(i+1)=p+6, p(i+2)=p+6+2, p(i+3)=p+6+2+4.

Extensions

Listed terms verified by Ray Chandler, Apr 20 2009

A079016 Suppose p and q = p+12 are primes. Define the difference pattern of (p,q) to be the successive differences of the primes in the range p to q. There are 14 possible difference patterns, namely [12], [2,10], [4,8], [6,6], [8,4], [10,2], [2,4,6], [2,6,4], [4,2,6], [4,6,2], [6,2,4], [6,4,2], [2,4,2,4] and [4,2,4,2]. Sequence gives smallest value of p for each difference pattern, sorted by magnitude.

Original entry on oeis.org

5, 7, 17, 19, 29, 31, 47, 67, 89, 137, 139, 199, 397, 1601
Offset: 1

Views

Author

Labos Elemer, Jan 24 2003

Keywords

Examples

			p=1601, q=1613 has difference pattern [6,2,4] and {1601,1607,1609,1613} is the corresponding consecutive prime 4-tuple.
		

Crossrefs

A022006(1)=5, A022007(1)=7, A078847(1)=17, A078851(1)=19, A078848(1)=29, A078855(1)=31, A047948(1)=47, A078850(1)=67, A031930(1)=A000230(6)=199, A046137(1)=7, A078853(1)=1601.

Programs

  • Mathematica
    Function[s, Function[t, Union@ Flatten@ Map[s[[First@ Position[t, #]]] &, {{12}, {2, 10}, {4, 8}, {6, 6}, {8, 4}, {10, 2}, {2, 4, 6}, {2, 6, 4}, {4, 2, 6}, {4, 6, 2}, {6, 2, 4}, {6, 4, 2}, {2, 4, 2, 4}, {4, 2, 4, 2}}]]@ Map[Differences@ Select[Range[#, # + 12], PrimeQ] &, s]]@ Select[Prime@ Range[10^3], PrimeQ[# + 12] &] (* Michael De Vlieger, Feb 25 2017 *)

A078953 Primes p such that the differences between the 5 consecutive primes starting with p are (4,2,6,4).

Original entry on oeis.org

67, 2377, 21487, 31177, 65167, 67927, 81547, 139297, 166597, 178597, 185527, 305017, 305407, 321817, 341947, 390487, 427417, 448867, 547357, 600877, 635347, 668527, 693727, 697507, 752287, 764887, 783787, 812347, 819487, 877867, 1196857, 1229197, 1262617, 1279177
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+4, p+6, p+12 and p+16 are consecutive primes.

Examples

			67 is in the sequence since 67, 71 = 67 + 4, 73 = 67 + 6, 79 = 67 + 12 and 83 = 67 + 16 are consecutive primes.
		

Crossrefs

Subsequence of A078850. - R. J. Mathar, Feb 11 2013

Programs

  • Mathematica
    Select[Partition[Prime[Range[50000]], 5, 1], Differences[#] == {4,2,6,4} &][[;;, 1]] (* Amiram Eldar, Feb 21 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 4 && p3 - p2 == 2 && p4 - p3 == 6 && p5 - p4 == 4, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025

Formula

a(n) == 7 (mod 30). - Amiram Eldar, Feb 21 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002
Previous Showing 11-13 of 13 results.