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 1-10 of 28 results. Next

A078946 Primes p such that p, p+2, p+6, p+12 and p+14 are consecutive primes.

Original entry on oeis.org

17, 227, 1277, 1607, 3527, 3917, 4637, 4787, 27737, 38447, 39227, 44267, 71327, 97367, 99707, 113147, 122027, 122387, 124337, 165707, 183497, 187127, 191447, 197957, 198827, 275447, 290657, 312197, 317957, 347057, 349397, 416387, 418337, 421697, 427067, 443867
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Examples

			227 is in the sequence since 227, 229 = 227 + 2, 233 = 227 + 6, 239 = 227 + 12 and 241 = 227 + 14 are consecutive primes.
		

Crossrefs

Subsequence of A128468.
Subsequence of A078847. - R. J. Mathar, Feb 10 2013

Programs

  • Magma
    [p: p in PrimesInInterval(7,1000000) | forall{i: i in [2,6,12,14] | IsPrime(p+i)}]; // Vincenzo Librandi, Apr 19 2015
  • Mathematica
    Rest@ Select[Prime@ Range@ 36000, AllTrue[{2, 6, 12, 14} + #, PrimeQ] &] (* Michael De Vlieger, Apr 18 2015, Version 10 *)
    Select[Partition[Prime[Range[36000]],5,1],Differences[#]=={2,4,6,2}&][[All,1]] (* Harvey P. Dale, Jun 14 2022 *)
  • PARI
    isok(p) = isprime(p) && (nextprime(p+1)==p+2) && (nextprime(p+3)== p+6) && (nextprime(p+7)==p+12) && (nextprime(p+13)==p+14); \\ Michel Marcus, Dec 10 2013
    
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 2 && p3 - p2 == 4 && p4 - p3 == 6 && p5 - p4 == 2, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025
    

Formula

a(n) == 17 (mod 30). - Amiram Eldar, Feb 21 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078866 The quadruples (d1,d2,d3,d4) with elements in {2,4,6} are listed in lexicographic order; for each quadruple, this sequence lists the smallest prime p >= 5 such that the differences between the 5 consecutive primes starting with p are (d1,d2,d3,d4), if such a prime exists.

Original entry on oeis.org

5, 17, 41, 29, 71, 149, 3299, 7, 13, 67, 1597, 19, 43, 12637, 1601, 23, 593, 31, 61, 3313, 157, 47, 601, 151, 251, 3301
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

The 26 quadruples for which p exists are listed, in decimal form, in A078868.

Examples

			The term 12637 corresponds to the quadruple (4,6,6,6): 12637, 12641, 12647, 12653 and 12659 are consecutive primes.
		

Crossrefs

The quadruples are in A078868. The same primes, in increasing order, are in A078867. The sequences of primes corresponding to the 26 difference patterns are in A022006, A022007 and A078946-A078970. Cf. A001223.

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078969 Primes p such that the differences between the 5 consecutive primes starting with p are (6,6,6,4).

Original entry on oeis.org

3301, 15901, 18211, 30091, 53611, 71341, 77551, 80911, 89101, 120811, 252151, 285451, 292471, 294781, 344251, 601801, 616501, 744811, 792691, 809821, 908521, 912391, 1152631, 1154221, 1279801, 1376491, 1398031, 1455361, 1464271, 1500511, 1503031, 1555111, 1594261
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+6, p+12, p+18 and p+22 are consecutive primes.

Examples

			30091 is in the sequence since 30091, 30097 = 30091 + 6, 30103 = 30091 + 12, 30109 = 30091 + 18 and 30113 = 30091 + 22 are consecutive primes.
		

Crossrefs

Subsequence of A033451. - R. J. Mathar, May 06 2017

Programs

  • Mathematica
    Select[Partition[Prime[Range[150000]], 5, 1], Differences[#] == {6,6,6,4} &][[;;, 1]] (* Amiram Eldar, Feb 22 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 6 && p3 - p2 == 6 && p4 - p3 == 6 && p5 - p4 == 4, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 22 2025

Formula

a(n) == 1 (mod 30). - Amiram Eldar, Feb 22 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078868 Decimal concatenations of the quadruples (d1,d2,d3,d4) with elements in {2,4,6} for which there exists a prime p >= 5 such that the differences between the 5 consecutive primes starting with p are (d1,d2,d3,d4).

Original entry on oeis.org

2424, 2462, 2466, 2642, 2646, 2664, 2666, 4242, 4246, 4264, 4624, 4626, 4662, 4666, 6246, 6264, 6266, 6424, 6426, 6462, 6466, 6626, 6642, 6646, 6662, 6664
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Examples

			4624 corresponds to the quadruple (4,6,2,4). It is in the sequence because the 5 consecutive primes 1597, 1601, 1607, 1609 and 1613 have differences (4,6,2,4).
		

Crossrefs

The least primes corresponding to the quadruples are in A078866. The same primes, in increasing order, are in A078867. The sequences of primes corresponding to the 26 difference patterns are in A022006 (for 2424), A022007 (for 4242) and A078946-A078970. The similarly defined quintuples are in A078870. Cf. A001223.

Programs

  • Mathematica
    With[{k = 4}, FromDigits /@ Select[Tuples[Range[2, 6, 2], k], Function[m, Count[Range[k, 10^k], n_ /; Times @@ Boole@ Map[PrimeQ, Prime@ n + Accumulate@ m] == 1] > 0]]] (* Michael De Vlieger, Mar 25 2017 *) (* or *)
    FromDigits /@ Union@ Select[ Partition[ Differences@ Prime@ Range[3, 2000], 4, 1], Max@ # <= 6 &] (* Giovanni Resta, Mar 25 2017 *)

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078875 Sorted version of A078874.

Original entry on oeis.org

11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 149, 151, 251, 587, 593, 1597, 1601, 2671, 3299, 3301, 4637, 5639, 5839, 5843, 17467, 19457, 32353, 41597, 44257, 71329, 71333, 78779, 130631, 135589, 135593, 179801, 246907, 302563, 326993, 351031, 435553, 603899, 678631, 6268957
Offset: 1

Views

Author

Labos Elemer, Dec 20 2002

Keywords

Comments

Each term is the smallest prime p >= 7 such that the differences between the 7 consecutive primes starting with p are (d1,d2,d3,d4,d5,d6), for some 6-tuple (d1,d2,d3,d4,d5,d6) with elements in {2,4,6}.

Examples

			The term 151 corresponds to the 6-tuple (6,6,4,6,6,2): 151, 157, 163, 167, 173, 179, 181 are consecutive primes.
		

Crossrefs

The 6-tuples are in A078871. The same primes, in lexicographic order of the 6-tuples, are in A078874. The analogous sequences for quadruples and quintuples are in A078867 and A078873. Cf. A001223.

Extensions

Edited by Dean Hickerson, Dec 21 2002

A078947 Primes p such that the differences between the 5 consecutive primes starting with p are (2,4,6,6).

Original entry on oeis.org

41, 641, 1091, 4001, 9461, 26681, 26711, 44531, 79811, 103991, 110921, 112571, 172421, 223241, 276821, 289841, 290021, 317771, 373181, 381371, 434921, 450881, 493121, 602081, 678761, 788351, 834131, 907211, 974861, 1076501, 1081121, 1097891, 1200371, 1409531, 1426151
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+2, p+6, p+12 and p+18 are consecutive primes.

Examples

			641 is in the sequence since 641, 643 = 641 + 2, 647 = 641 + 6, 653 = 641 + 12 and 659 = 641 + 18 are consecutive primes.
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[50000]], 5, 1], Differences[#] == {2, 4, 6, 6} &][[;;, 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 == 2 && p3 - p2 == 4 && p4 - p3 == 6 && p5 - p4 == 6, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025

Formula

a(n) == 11 (mod 30). - Amiram Eldar, Feb 21 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078873 Sorted version of A078872.

Original entry on oeis.org

7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 59, 61, 67, 149, 151, 157, 251, 587, 593, 599, 1597, 1601, 1861, 2333, 2671, 3299, 3301, 3307, 4639, 5849, 6353, 6959, 14731, 17467, 32353, 90001
Offset: 1

Views

Author

Labos Elemer, Dec 20 2002

Keywords

Comments

Each term is the smallest prime p >= 7 such that the differences between the 6 consecutive primes starting with p are (d1,d2,d3,d4,d5), for some quintuple (d1,d2,d3,d4,d5) with elements in {2,4,6}.

Examples

			The term 90001 corresponds to the quadruple (6,4,6,2,4): 90001, 90007, 90011, 90017, 90019, 90023 are consecutive primes.
		

Crossrefs

The quintuples are in A078870. The same primes, in lexicographic order of the quintuples, are in A078872. The analogous sequences for quadruples and 6-tuples are in A078867 and A078875. Cf. A001223.

Extensions

Edited by Dean Hickerson, Dec 21 2002

A078948 Primes p such that the differences between the 5 consecutive primes starting with p are (2,6,4,2).

Original entry on oeis.org

29, 59, 269, 1289, 2129, 2789, 5639, 8999, 13679, 14549, 18119, 36779, 62129, 75989, 80669, 83219, 88799, 93479, 113159, 115769, 124769, 132749, 150209, 160079, 163979, 203309, 207509, 223829, 228509, 278489, 282089, 284729, 298679, 312929, 313979, 323369, 337859
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+2, p+8, p+12 and p+14 are consecutive primes.
All terms are congruent to 29 (mod 30). - Muniru A Asiru, Sep 04 2017

Examples

			59 is in the sequence since 59, 61 = 59 + 2, 67 = 59 + 8, 71 = 59 + 12 and 73 = 59 + 14 are consecutive primes.
		

Crossrefs

Subsequence of A078848. - R. J. Mathar, Feb 10 2013

Programs

  • GAP
    K:=26*10^7+1;; # to get all terms <= K.
    P:=Filtered([1,3..K],IsPrime);;  I:=[2,6,4,2];;
    P1:=List([1..Length(P)-1],i->P[i+1]-P[i]);;
    Q:=List(Positions(List([1..Length(P)-Length(I)],i->[P1[i],P1[i+1],P1[i+2],P1[i+3]]),I),i->P[i]); # Muniru A Asiru, Sep 04 2017
    
  • Maple
    for i from 1 to 10^5 do if [ithprime(i+1),ithprime(i+2),ithprime(i+3),ithprime(i+4)] = [ithprime(i)+2,ithprime(i)+8,ithprime(i)+12,ithprime(i)+14] then print(ithprime(i)); fi; od;  # Muniru A Asiru, Sep 04 2017
  • Mathematica
    Select[Partition[Prime[Range[26000]],5,1],Differences[#]=={2,6,4,2}&][[;;,1]] (* Harvey P. Dale, Dec 10 2024 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 2 && p3 - p2 == 6 && p4 - p3 == 4 && p5 - p4 == 2, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078949 Primes p such that the differences between the 5 consecutive primes starting with p are (2,6,4,6).

Original entry on oeis.org

71, 431, 2339, 2381, 5849, 6959, 27791, 32561, 41609, 45119, 46439, 48479, 51419, 54401, 63599, 78779, 81551, 106859, 115319, 130631, 138569, 143501, 153269, 166601, 183569, 196169, 204359, 229751, 246929, 266081, 279119, 321311, 326999, 350729, 357659, 362741
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+2, p+8, p+12 and p+18 are consecutive primes.

Examples

			71 is in the sequence since 71, 73 = 71 + 2, 79 = 71 + 8, 83 = 71 + 12 and 89 = 71 + 18 are consecutive primes.
		

Crossrefs

Subsequence of A078848. - R. J. Mathar, Feb 10 2013

Programs

  • Mathematica
    Select[Partition[Prime[Range[50000]], 5, 1], Differences[#] == {2, 6, 4, 6} &][[;;, 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 == 2 && p3 - p2 == 6 && p4 - p3 == 4 && p5 - p4 == 6, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025

Formula

From Amiram Eldar, Feb 21 2025: (Start)
a(n) == 5 (mod 6).
a(n) == 11 or 29 (mod 30). (End)

Extensions

Edited by Dean Hickerson, Dec 20 2002

A078950 Primes p such that the differences between the 5 consecutive primes starting with p are (2,6,6,4).

Original entry on oeis.org

149, 599, 27059, 31319, 42179, 65699, 75209, 85829, 87539, 92219, 135599, 170759, 205949, 221069, 249419, 274829, 278609, 280589, 287849, 302579, 307259, 308309, 350429, 355499, 398339, 406499, 416399, 422549, 541529, 566549, 573479, 585839, 603899, 609599, 637709
Offset: 1

Views

Author

Labos Elemer, Dec 19 2002

Keywords

Comments

Equivalently, primes p such that p, p+2, p+8, p+14 and p+18 are consecutive primes.

Examples

			149 is in the sequence since 149, 151 = 149 + 2, 157 = 149 + 8, 163 = 149 + 14 and 167 = 149 + 18 are consecutive primes.
		

Crossrefs

Subsequence of A078849. - R. J. Mathar, May 06 2017

Programs

  • Mathematica
    Select[Partition[Prime[Range[50000]], 5, 1], Differences[#] == {2, 6, 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 == 2 && p3 - p2 == 6 && p4 - p3 == 6 && p5 - p4 == 4, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 21 2025

Formula

a(n) == 29 (mod 30). - Amiram Eldar, Feb 21 2025

Extensions

Edited by Dean Hickerson, Dec 20 2002
Showing 1-10 of 28 results. Next