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 1-9 of 9 results.

A022008 Initial member of prime sextuples (p, p+4, p+6, p+10, p+12, p+16).

Original entry on oeis.org

7, 97, 16057, 19417, 43777, 1091257, 1615837, 1954357, 2822707, 2839927, 3243337, 3400207, 6005887, 6503587, 7187767, 7641367, 8061997, 8741137, 10526557, 11086837, 11664547, 14520547, 14812867, 14834707, 14856757, 16025827, 16094707, 18916477, 19197247
Offset: 1

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Author

Keywords

Comments

Without the initial 7, this gives primes at which difference pattern X42424Y (X and Y >= 8) occurs in A001223. - Labos Elemer
Subsequence of A022007. - Zak Seidov, Nov 01 2011
From Jean-Christophe Hervé, Sep 27 2014: (Start)
The primes in a sextuple a(n), a(n)+4, a(n)+6, a(n)+10, a(n)+12, a(n)+16 are consecutive since a(n)+2, a(n)+8 and a(n)+14 cannot be prime (multiple of 3).
The prime sextuples starting at a(n) give the highest concentration of primes that can occur on an interval of 17 integers (apart intervals starting at p < 7). It is conjectured that there are infinitely many such sextuples.
For n > 1, the 3 odd integers preceding and the 3 odd integers following the sextuple are not prime: a(n)-2 == a(n)+18 == 0 (mod 5), a(n)-4 == a(n)+20 == 0 (mod 3), a(n)-6 == a(n)+22 == 0 (mod 7) and thus a(n) == 97 (mod 210 = 2*3*5*7). (End)
All terms are congruent to 7 (mod 30). - Zak Seidov, May 07 2017
All terms but the first one are congruent to 97 (mod 210). - M. F. Hasler, Jan 18 2022

Examples

			n=2: 97, 101, 103, 107, 109, 113 are consecutive primes, while 91, 93, 95 and 115, 117 and 119 are not (cf. 4th comment about the border of composites).
		

Crossrefs

Cf. A022007.
Cf. A350826 (number of n-digit terms).

Programs

  • GAP
    P:=Filtered([1,3..2*10^7+1],IsPrime);;  I:=[4,2,4,2,4];;
    P1:=List([1..Length(P)-1],i->P[i+1]-P[i]);;
    A022008:=List(Positions(List([1..Length(P)-Length(I)],i->[P1[i],P1[i+1],P1[i+2],P1[i+3],P1[i+4]]),I),j->P[j]); # Muniru A Asiru, Sep 03 2017
  • Magma
    [p: p in PrimesUpTo(2*10^7) | IsPrime(p+4) and IsPrime(p+6) and IsPrime(p+10)and IsPrime(p+12) and IsPrime(p+16)]; // Vincenzo Librandi, Aug 23 2015
    
  • Maple
    for i from 1 to 2*10^5 do if [ithprime(i+1), ithprime(i+2), ithprime(i+3), ithprime(i+4), ithprime(i+5)] = [ithprime(i)+4,ithprime(i)+6,ithprime(i)+10,ithprime(i)+12,ithprime(i)+16] then print(ithprime(i)); fi; od; # Muniru A Asiru, Sep 03 2017
  • Mathematica
    lst = {}; Do[p = Prime[n]; If[PrimeQ[p+4] && PrimeQ[p+6] && PrimeQ[p+10] && PrimeQ[p+12] && PrimeQ[p+16], AppendTo[lst, p]], {n, 1000000}]; lst
    Transpose[Select[Partition[Prime[Range[10^6]],6,1],Differences[#]=={4,2,4,2,4}&]][[1]] (* Harvey P. Dale, Mar 15 2015 *)
  • PARI
    p=2;q=3;r=5;s=7;t=11;forprime(u=13,1e9,if(u-p==16 && p%3==1, print1(p", "));p=q;q=r;r=s;s=t;t=u) \\ Charles R Greathouse IV, Mar 29 2013
    
  • PARI
    {next_A022008(p, L=Vec(p+1,5), m=210, r=Mod(97,m))=for(i=1,oo, L[i%5+1]+16==(p=nextprime(p+1))&&break; p%m>111 && until(r==p=nextprime((p+8)\/210*210+97),); L[i%5+1]=p); p-16} \\ M. F. Hasler, Jan 18 2022
    
  • Perl
    use ntheory ":all"; say for sieve_prime_cluster(1,1e8, 4,6,10,12,16); # Dana Jacobsen, Sep 30 2015
    

A052378 Primes followed by a [4,2,4] prime difference pattern of A001223.

Original entry on oeis.org

7, 13, 37, 97, 103, 223, 307, 457, 853, 877, 1087, 1297, 1423, 1483, 1867, 1993, 2683, 3457, 4513, 4783, 5227, 5647, 6823, 7873, 8287, 10453, 13687, 13873, 15727, 16057, 16063, 16183, 17383, 19417, 19423, 20743, 21013, 21313, 22273, 23053, 23557
Offset: 1

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Author

Labos Elemer, Mar 22 2000

Keywords

Comments

The sequence includes A052166, A052168, A022008 and also other primes like 13, 103, 16063 etc.
a(n) is the lesser term of a 4-twin (A023200) after which the next 4-twin comes in minimal distance [here it is 2; see A052380(4/2)].
Analogous prime sequences are A047948, A052376, A052377 and A052188-A052198 with various [d, A052380(d/2), d] difference patterns following a(n).
All terms == 1 (mod 6) - Zak Seidov, Aug 27 2012
Subsequence of A022005. - R. J. Mathar, May 06 2017

Examples

			103 initiates [103,107,109,113] prime quadruple followed by [4,2,4] difference pattern.
		

Crossrefs

Programs

  • Mathematica
    a = {}; Do[If[Prime[x + 3] - Prime[x] == 10, AppendTo[a, Prime[x]]], {x, 1, 10000}]; a (* Zerinvary Lajos, Apr 03 2007 *)
    Select[Partition[Prime[Range[3000]],4,1],Differences[#]=={4,2,4}&][[All,1]] (* Harvey P. Dale, Jun 16 2017 *)
  • PARI
    is(n)=n%6==1 && isprime(n+4) && isprime(n+6) && isprime(n+10) && isprime(n) \\ Charles R Greathouse IV, Apr 29 2015

Formula

a(n) is the initial prime of a [p, p+4, p+6, p+6+4] prime-quadruple consisting of two 4-twins: [p, p+4] and [p+6, p+10].

A102332 Initial prime p introducing a prime sextuplet of consecutive primes as follows: {p, p+10, p+18, p+28, p+36, p+46} with the corresponding prime-difference-pattern is {10,8,10,8,10}.

Original entry on oeis.org

37861, 39181, 324763, 692743, 810391, 945331, 1047961, 1429573, 1513573, 1540813, 1799071, 3463573, 3861223, 3979201, 4536121, 4641001, 5154343, 5445403, 5874853, 7851583, 8820793, 8961373, 8976403, 9302113, 9673351, 10323133, 11074033, 11136883, 11899333, 13505983
Offset: 1

Views

Author

Labos Elemer, Jan 06 2005

Keywords

Comments

A generalization of primes displayed in A022008.

Crossrefs

Programs

  • Mathematica
    tm=TimeUsed[];ta={{0}};Do[g=n;d1=10;d2=8;d3=10;d4=8;d5=10; s1=Prime[n+1]-Prime[n];s2=Prime[n+2]-Prime[n+1]; s3=Prime[n+3]-Prime[n+2];s4=Prime[n+4]-Prime[n+3]; s5=Prime[n+5]-Prime[n+4];If[Equal[s1, d1]&&Equal[s2, d2]&& Equal[s3, d3]&&Equal[s4, d4]&&Equal[s5, d5], Print[{Prime[n], s1, s2, s3, s4, s5}];ta=Append[ta, Prime[n]]], {n, 1, 10000000}] {ta=Delete[ta, 1], {d1, d2}} {g, TimeUsed[]-tm}
    Transpose[Select[Partition[Prime[Range[650000]],6,1],Differences[#]=={10,8,10,8,10}&]][[1]] (* Harvey P. Dale, Oct 18 2013 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7, p5 = 11); forprime(p6 = 13, lim, if(p2 - p1 == 10 && p3 - p2 == 8 && p4 - p3 == 10 && p5 - p4 == 8 && p6 - p5 == 10, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5; p5 = p6);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 1 (mod 6). - Amiram Eldar, Feb 18 2025

Extensions

Definition corrected by Harvey P. Dale, Oct 18 2013

A102333 Initial terms of quartets of consecutive primes as follows: {p, p+16, p+24, p+40}. The corresponding difference-pattern is {16,8,16}.

Original entry on oeis.org

108247, 121507, 166783, 169567, 178207, 216133, 257053, 258763, 272863, 274123, 372613, 383533, 384343, 396157, 413143, 501577, 562477, 577153, 581353, 635293, 721267, 727273, 738937, 769903, 908113, 917713, 932497, 937903, 965467, 980377, 989647, 1008547, 1126537
Offset: 1

Views

Author

Labos Elemer, Jan 06 2005

Keywords

Comments

A generalization of A052378.

Crossrefs

Programs

  • Mathematica
    Transpose[Select[Partition[Prime[Range[78000]],4,1],Differences[#] == {16,8,16}&]][[1]] (* Harvey P. Dale, Mar 18 2012 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5); forprime(p4 = 7, lim, if(p2 - p1 == 16 && p3 - p2 == 8 && p4 - p3 == 16, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 1 (mod 6). - Amiram Eldar, Feb 18 2025

A102334 Initial terms of quintuplets of consecutive primes as follows: {p, p+16, p+24, p+40, p+48}. The corresponding difference-pattern is {16,8,16,8}.

Original entry on oeis.org

272863, 274123, 372613, 1394893, 1634293, 2380423, 3846373, 5298523, 5358013, 5797903, 6741913, 7554823, 7647643, 7716103, 7738153, 8241463, 8358283, 9710473, 9859783, 12454333, 12510193, 12796423, 13710133, 14477893, 15162493, 15186583, 15263503, 15603853, 16438243, 16771933, 17913283, 18957973, 19373623
Offset: 1

Views

Author

Labos Elemer, Jan 06 2005

Keywords

Comments

A generalization of A022007.

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[1233300]], 5, 1], Differences[#] == {16, 8, 16, 8} &][[;;, 1]] (* Amiram Eldar, Feb 18 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 16 && p3 - p2 == 8 && p4 - p3 == 16 && p5 - p4 == 8, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 13 (mod 30). - Amiram Eldar, Feb 18 2025

Extensions

Missing terms a(1)-a(11) inserted by Amiram Eldar, Feb 18 2025

A102335 Initial terms of sextuplets of consecutive primes as follows: {p, p+16, p+24, p+40, p+48, p+64}. The corresponding difference-pattern is {16,8,16,8,16}.

Original entry on oeis.org

12454333, 21228553, 25131193, 38589673, 41426353, 46254253, 56564623, 60498133, 61151863, 96691213, 158497153, 169760713, 182960473, 201513133, 226086283, 236031463, 253806913, 290686483, 305472373, 344550643, 369110983, 380973253, 421335883, 445537333, 461955763
Offset: 1

Views

Author

Labos Elemer, Jan 06 2005

Keywords

Comments

A generalization of A022008. The generalized pattern of consecutive prime-differences is {6a+4, 6b+2, 6c+4, 6d+2, 6e+4} with a = c = e = 2, b = d = 1.

Crossrefs

Programs

  • Mathematica
    Transpose[Select[Partition[Prime[Range[20000000]],6,1],Differences[#] == {16,8,16,8,16}&]][[1]] (* Harvey P. Dale, Nov 08 2011 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7, p5 = 11); forprime(p6 = 13, lim, if(p2 - p1 == 16 && p3 - p2 == 8 && p4 - p3 == 16 && p5 - p4 == 8 && p6 - p5 == 16, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5; p5 = p6);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 73 (mod 210). - Amiram Eldar, Feb 18 2025

A102331 Initial members of quintuplets (p, p+4, p+12, p+16, p+24) of consecutive primes with the corresponding difference pattern is {4,8,4,8}.

Original entry on oeis.org

13147, 14407, 114757, 132607, 231547, 353317, 459607, 476587, 568987, 601747, 652357, 724627, 794137, 861547, 904777, 1010407, 1094437, 1140847, 1147567, 1170007, 1270417, 1424557, 1441327, 1477027, 1604497, 1646287, 1673377, 2043397, 2078707, 2126767, 2130367
Offset: 1

Views

Author

Labos Elemer, Jan 07 2005

Keywords

Comments

Generalization of A022007. These primes are congruent to 7 modulo 10, so the realization of longer prime-difference pattern = {4,8,4,8,4} is not already possible because the sum = 4+8+4+8+4 = 28. Consequently, 10k+7+28 = 10m+5 cannot be a prime. Thus analogous generalization of A022008 is possible only with restrictions. See also Comment in A102335.

Examples

			The prime 13147 is followed by the primes {13151, 13159, 13163, 13171}. Observe that these patterns start and end with primes of the form 10k+7 and 10m+1, respectively.
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[158000]], 5, 1], Differences[#] == {4, 8, 4, 8} &][[;;, 1]] (* Amiram Eldar, Feb 18 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 4 && p3 - p2 == 8 && p4 - p3 == 4 && p5 - p4 == 8, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 7 (mod 30). - Amiram Eldar, Feb 18 2025

A102336 Initial members of quintuplets (p, p+4, p+12, p+28, p+60) of consecutive primes with the corresponding difference pattern is {4,8,16,32}.

Original entry on oeis.org

1197739, 2496409, 2692549, 2962489, 3195679, 5723479, 6824899, 7706059, 8056039, 8337319, 10132609, 10583269, 11739589, 12167509, 12674659, 13007959, 13699459, 14148049, 14252929, 14702839, 15726019, 16694539, 17115949, 17282299, 17350159, 17584729, 18065389, 18097609
Offset: 1

Views

Author

Labos Elemer, Jan 07 2005

Keywords

Comments

Generalization of A022007. These primes are congruent to 9 modulo 10, while terminal entry of 5-tuple has the form 10s+9.

Examples

			1197739 is a prime, followed by (1197743, 1197751, 1197767, 1197799) with consecutive prime difference pattern: {4,8,16,32}.
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[10^6]], 5, 1], Differences[#] == 2^Range[2, 5] &][[;;, 1]] (* Amiram Eldar, Feb 18 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7); forprime(p5 = 11, lim, if(p2 - p1 == 4 && p3 - p2 == 8 && p4 - p3 == 16 && p5 - p4 == 32, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 19 (mod 30). - Amiram Eldar, Feb 18 2025

A102337 Initial members of sextuplets (p, p+4, p+12, p+28, p+60, p+124) of consecutive primes with the corresponding difference pattern is {4,8,16,32,64}.

Original entry on oeis.org

166392559, 337149859, 1356705139, 1455488059, 1879518709, 2339605519, 2410687039, 2811378079, 3191346019, 3250560139, 3442915309, 3573582079, 4873308619, 4875167959, 5362448719, 5524743379, 5580251359, 5716641649, 5783545759, 5977816549, 6019275469, 6076905349
Offset: 1

Views

Author

Labos Elemer, Jan 07 2005

Keywords

Comments

Generalization of A022008 because the relevant prime-difference pattern has the following form: (4+6a,2+6b,4+6c,2+6d,4+6e), a = 0, b = 1, c = 2, d = 5, e = 10. The primes are congruent to 9 modulo 10, while terminal entries of the quintuplets have the form 10s+3.

Examples

			1455488059 is a prime, followed by consecutive prime difference pattern: {4,8,16,32,64}. The terminal prime is 1455488183.
		

Crossrefs

Programs

  • Mathematica
    Select[Partition[Prime[Range[3*10^7]], 6, 1], Differences[#] == 2^Range[2, 6] &][[;;, 1]] (* Amiram Eldar, Feb 18 2025 *)
  • PARI
    list(lim) = {my(p1 = 2, p2 = 3, p3 = 5, p4 = 7, p5 = 11); forprime(p6 = 13, lim, if(p2 - p1 == 4 && p3 - p2 == 8 && p4 - p3 == 16 && p5 - p4 == 32 && p6 - p5 == 64, print1(p1, ", ")); p1 = p2; p2 = p3; p3 = p4; p4 = p5; p5 = p6);} \\ Amiram Eldar, Feb 18 2025

Formula

a(n) == 19 (mod 30). - Amiram Eldar, Feb 18 2025

Extensions

a(5)-a(18) from Donovan Johnson, Apr 17 2010
a(19)-a(22) from Amiram Eldar, Feb 18 2025
Showing 1-9 of 9 results.