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

A078850 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=[4,2,6]; short d-string notation of pattern = [426].

Original entry on oeis.org

67, 1447, 2377, 2707, 5437, 5737, 7207, 9337, 11827, 12037, 19207, 21487, 21517, 23197, 26107, 26947, 28657, 31147, 31177, 35797, 37357, 37567, 42697, 50587, 52177, 65167, 67927, 69997, 71707, 74197, 79147, 81547, 103087, 103387, 106657
Offset: 1

Views

Author

Labos Elemer, Dec 11 2002

Keywords

Comments

Subsequence of A022005. - R. J. Mathar, May 06 2017

Examples

			p=67,67+4=71,67+4+2=73,67+4+2+6=79 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], A078853[624], A078854[626], A078855[642], A078856[646], A078857[662], A078858[664], A033451[666].

Programs

  • Mathematica
    d = {4, 2, 6}; First /@ Select[Partition[Prime@ Range@ 12000, Length@ d + 1, 1], Differences@ # == d &] (* Michael De Vlieger, May 02 2016 *)

Formula

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

Extensions

Listed terms verified by Ray Chandler, Apr 20 2009

A190814 Initial primes of 5 consecutive primes with consecutive gaps 2, 4, 6, 8.

Original entry on oeis.org

347, 1427, 2687, 4931, 13901, 21557, 23741, 27941, 28277, 31247, 32057, 33617, 45821, 55661, 55817, 68207, 68897, 91571, 128657, 128981, 167621, 179897, 193871, 205421, 221717, 234191, 239231, 258107, 258611, 259157, 278807, 302831, 305477, 348431, 354371
Offset: 1

Views

Author

Zak Seidov, May 20 2011

Keywords

Comments

All terms = {11,17} mod 30.
a(n) + 20 is the greatest term in the sequence of 5 consecutive primes with 4 consecutive gaps 2, 4, 6, 8. - Muniru A Asiru, Aug 03 2017

Examples

			Prime(69..73) = {347, 349, 353, 359, 367} and 349 - 347 = 2, 353 - 349 = 4, 359 - 353 = 6, 367 - 359 = 8.
		

Crossrefs

Subsequence of A190799, also subsequence of A078847.

Programs

  • Maple
    N:= 10^6: # to get all terms <= N
    Primes:= select(isprime, [seq(i,i=3..N+20,2)]):
    Primes[select(t -> [Primes[t+1]-Primes[t],Primes[t+2]-Primes[t+1],Primes[t+3]-Primes[t+2],Primes[t+4]-Primes[t+3]] = [2,4,6,8], [$1..nops(Primes)-4])]; # Robert Israel, Aug 03 2017
  • Mathematica
    d = Differences[Prime[Range[100000]]]; Prime[Flatten[Position[Partition[d, 4, 1], {2, 4, 6, 8}]]] (* T. D. Noe, May 23 2011 *)
    Select[Partition[Prime[Range[31000]],5,1],Differences[#]=={2,4,6,8}&][[All,1]] (* Harvey P. Dale, Jul 03 2020 *)

Extensions

Additional cross references from Harvey P. Dale, May 10 2014

A190817 Initial primes of 6 consecutive primes with consecutive gaps 2,4,6,8,10.

Original entry on oeis.org

13901, 21557, 28277, 55661, 68897, 128981, 221717, 354371, 548831, 665111, 954257, 1164587, 1246367, 1265081, 1538081, 1595051, 1634441, 2200811, 2798921, 2858621, 3053747, 3407081, 3414011, 3967487, 3992201, 4480241, 4608281, 4701731, 4809251, 5029457
Offset: 1

Views

Author

Zak Seidov, May 21 2011

Keywords

Comments

a(1) = 13901 = A190814(5) = A187058(7) = A078847(24).
a(n) + 30 is the greatest term in the sequence of 6 consecutive primes with consecutive gaps 2, 4, 6, 8, 10. - Muniru A Asiru, Aug 10 2017

Examples

			For n = 1, 13901 is in the sequence because 13901, 13903, 13907, 13913, 13921, 13931 are consecutive primes and for n = 2, 21557 is in the sequence since 21557, 21559, 21563, 21569, 21577, 21587 are consecutive primes. - _Muniru A Asiru_, Aug 24 2017
		

Crossrefs

Programs

  • GAP
    K:=3*10^7+1;; # to get all terms <= K.
    P:=Filtered([1,3..K],IsPrime);; I:=[2,4,6,8,10];;
    P1:=List([1..Length(P)-1],i->P[i+1]-P[i]);;
    P2:=List([1..Length(P)-Length(I)],i->[P1[i],P1[i+1],P1[i+2],P1[i+3],P1[i+4]]);;
    P3:=List(Positions(P2,I),i->P[i]);  # Muniru A Asiru, Aug 24 2017
  • Maple
    N:=10^7: # to get all terms <= N.
    Primes:=select(isprime,[seq(i,i=3..N+30,2)]):
    Primes[select(t->[Primes[t+1]-Primes[t], Primes[t+2]-Primes[t+1],Primes[t+3]-Primes[t+2], Primes[t+4]-Primes[t+3], Primes[t+5]-Primes[t+4]]=[2,4,6,8,10], [$1..nops(Primes)-5])]; # Muniru A Asiru, Aug 04 2017
  • Mathematica
    d = Differences[Prime[Range[100000]]]; Prime[Flatten[Position[Partition[d, 5, 1], {2, 4, 6, 8, 10}]]] (* T. D. Noe, May 23 2011 *)
    With[{s = Differences@ Prime@ Range[10^6]}, Prime[SequencePosition[s, Range[2, 10, 2]][[All, 1]] ] ] (* Michael De Vlieger, Aug 16 2017 *)
  • PARI
    lista(nn) = forprime(p=13901, nn, if(nextprime(p+1)==p+2 && nextprime(p+3)==p+6 && nextprime(p+7)==p+12 && nextprime(p+13)==p+20 && nextprime(p+21)==p+30, print1(p", "))); \\ Altug Alkan, Aug 16 2017
    

Extensions

Additional cross references from Harvey P. Dale, May 10 2014

A190819 Initial primes of 7 consecutive primes with consecutive gaps 2, 4, 6, 8, 10, 12.

Original entry on oeis.org

128981, 665111, 2798921, 3992201, 5071667, 5093507, 5344247, 10732817, 11920367, 16197947, 16462541, 16655447, 16943471, 21456047, 25793897, 32634311, 34051007, 34864211, 35250431, 38585201, 39898757, 49584371, 50375861, 51867197, 54738767, 55793951
Offset: 1

Views

Author

Zak Seidov, May 21 2011

Keywords

Comments

Subsequence of A190817, a(1) = 128981 = A190817(6).
a(n) + 42 is the greatest term in the sequence of 7 consecutive primes with 6 consecutive gaps 2, 4, 6, 8, 10, 12. - Muniru A Asiru, Aug 10 2017

Examples

			Prime(12073..12079) = {128981, 128983, 128987, 128993, 129001, 129011, 129023} with first differences {2, 4, 6, 8, 10, 12}.
		

Crossrefs

Programs

  • Maple
    N:=10^7: # to get all terms <= N.
    Primes:=select(isprime,[seq(i,i=3..N+42,2)]):
    Primes[select(t->[Primes[t+1]-Primes[t], Primes[t+2]-Primes[t+1],
    Primes[t+3]-Primes[t+2], Primes[t+4]-Primes[t+3], Primes[t+5]-Primes[t+4], Primes[t+6]-Primes[t+5] ]=[2,4,6,8,10,12], [$1..nops(Primes)-6])]; # Muniru A Asiru, Aug 04 2017
  • Mathematica
    d = Differences[Prime[Range[1000000]]]; Prime[Flatten[Position[Partition[d, 6, 1], {2, 4, 6, 8, 10, 12}]]] (* T. D. Noe, May 23 2011 *)
    Prime[SequencePosition[Differences[Prime[Range[34*10^5]]],{2,4,6,8,10,12}][[All,1]]] (* Harvey P. Dale, Feb 18 2022 *)

Extensions

Additional cross references from Harvey P. Dale, May 10 2014

A190838 Initial primes of 8 consecutive primes with 7 consecutive gaps 2, 4, 6, 8, 10, 12, 14.

Original entry on oeis.org

128981, 21456047, 34864211, 51867197, 55793951, 69726647, 113575727, 180078317, 207664397, 232728647, 342241967, 382427027, 382533311, 470463011, 558791327, 591360851, 603413801, 749930717, 838115711, 926976431, 965761397, 1007421251, 1109867567, 1278189947
Offset: 1

Views

Author

Zak Seidov, May 21 2011

Keywords

Comments

a(1) = 128981 = A190819(1), a(2) = 21456047 = A190819(14).
a(n) + 56 is the greatest term in the sequence of 8 consecutive primes with 7 consecutive gaps 2, 4, 6, 8, 10, 12, 14. - Muniru A Asiru, Aug 10 2017

Crossrefs

Subsequence of A190819.
Subsequence of A187060. - Michel Marcus, Aug 10 2017

Programs

  • Maple
    N:=10^8:  # to get all terms <= N.
    Primes:=select(isprime,[seq(i,i=3..N+56,2)]):
    Primes[select(t->[Primes[t+1]-Primes[t], Primes[t+2]-Primes[t+1],
      Primes[t+3]-Primes[t+2], Primes[t+4]-Primes[t+3], Primes[t+5]-
      Primes[t+4], Primes[t+6]-Primes[t+5] , Primes[t+7]-Primes[t+6] ]=
    [2,4,6,8,10,12,14], [$1..nops(Primes)-7])]; # Muniru A Asiru, Aug 04 2017
  • Mathematica
    Transpose[Select[Partition[Prime[Range[65000000]],8,1],Differences[#] =={2,4,6,8,10,12,14}&]][[1]] (* Harvey P. Dale, May 10 2014 *)
  • PARI
    list(lim)=my(v=List(),p=128981,t); forprime(q=p+2,lim+56, if(q-p-t==2, t+=2; if(t==14, listput(v, q-56); t=0), t=0); p=q); Vec(v) \\ Charles R Greathouse IV, Aug 10 2017

Extensions

Additional cross references from Harvey P. Dale, May 10 2014

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 *)

A190792 Primes p=prime(i) such that prime(i+3)-prime(i)=12.

Original entry on oeis.org

17, 19, 29, 31, 41, 59, 61, 67, 71, 127, 227, 229, 269, 271, 347, 431, 607, 641, 1009, 1091, 1277, 1279, 1289, 1291, 1427, 1447, 1487, 1597, 1601, 1607, 1609, 1657, 1777, 1861, 1987, 2129, 2131, 2339, 2371, 2377, 2381, 2539, 2677, 2687, 2707, 2789, 2791
Offset: 1

Views

Author

Zak Seidov, May 20 2011

Keywords

Comments

Minimal distance between prime(i) and prime(i+3) is 12 if all three consecutive prime gaps are different.
There are 6 possible consecutive prime gap configurations:
{2,4,6}, {2,6,4}, {4,2,6}, {4,6,2}, {6,2,4}, and {6,4,2}.
Least prime quartets with such gap configurations are:
{17,19,23,29}->{2,4,6}
{29,31,37,41}->{2,6,4}
{67,71,73,79}->{4,2,6}
{19,23,29,31}->{4,6,2}
{1601,1607,1609,1613}->{6,2,4}
{31,37,41,43}->{6,4,2}.

Crossrefs

Programs

  • Magma
    [NthPrime(i): i in [2..60000] | NthPrime(i+3)-NthPrime(i) eq 12];  // _Bruno Berselli-, May 20 2011
    
  • Mathematica
    p = Prime[Range[1000]]; First /@ Select[Partition[p, 4, 1], Last[#] - First[#] == 12 &] (* T. D. Noe, May 23 2011 *)
  • PARI
    is(n)=if(!isprime(n), return(0)); my(p=nextprime(n+1),q); if(p-n>6, return(0)); q=nextprime(p+1); q-n<11 && nextprime(q+1)-n==12 \\ Charles R Greathouse IV, Sep 14 2015

A290161 Initial primes of 7 consecutive primes with 6 consecutive gaps 12, 10, 8, 6, 4, 2.

Original entry on oeis.org

752251, 1107751, 4956781, 5647471, 6929401, 10016521, 11516851, 12285631, 18117991, 19280311, 21327961, 21705517, 23946877, 24059011, 24436891, 25976611, 26970751, 29105731, 32254471, 32339521, 32465077, 32542387
Offset: 1

Views

Author

Muniru A Asiru, Jul 22 2017

Keywords

Comments

All terms = {1,7} mod 30.
For initial primes of 7 consecutive primes with consecutive gaps 2, 4, 6, 8, 10, 12 see A190819.

Examples

			Prime(86279..86285) = {1107751, 1107763, 1107773, 1107781, 1107787, 1107791, 1107793 } and 1107751 + 12 = 1107763, 110763 + 10 = 1107773, 1107773 + 8 = 1107781, 1107781 + 6 = 1107787, 1107787 + 4 = 1107791, 1107791 + 2 = 1107793.
		

Crossrefs

Programs

  • GAP
    P:=Filtered([1..100000000],IsPrime);; I:=Reversed([2,4,6,8,10,12]);;
    P1:=List([1..Length(P)-1],i->P[i+1]-P[i]);;
    P2:=List([1..Length(P)-Length(I)],i->[P1[i],P1[i+1],P1[i+2],P1[i+3],P1[i+4],P1[i+5]]);;
    P3:=List(Positions(P2,I),i->P[i]);

A290162 Initial primes of 8 consecutive primes with 7 consecutive gaps 14, 12, 10, 8, 6, 4, 2.

Original entry on oeis.org

5647457, 18117977, 21705503, 32465063, 37091597, 57269633, 90217163, 109933673, 111053573, 124123133, 145594583, 146742863, 163123997, 200416343, 239659907, 245333267, 272213813, 335971367, 350795033, 470838833, 701465327, 749927357, 888801707, 1060690667
Offset: 1

Views

Author

Muniru A Asiru, Jul 22 2017

Keywords

Comments

All terms = {17,23} mod 30.
For initial primes of 8 consecutive primes with consecutive gaps 2, 4, 6, 8, 10, 12, 14 see A190838.

Examples

			Prime(390215..390222) = {5647457, 5647471, 5647483, 5647493, 5647501, 5647507, 5647511, 5647513} and 5647457 + 14 = 5647471, 5647471 + 12 = 5647483, 5647483 + 10 = 5647493, 5647493 + 8 = 5647501, 5647501 + 6 = 5647507, 5647507 + 4 = 5647511, 5647511 + 2 = 5647513.
		

Crossrefs

Programs

  • GAP
    P:=Filtered([1..100000000],IsPrime);; I:=Reversed([2,4,6,8,10,12,14]);;
    P1:=List([1..Length(P)-1],i->P[i+1]-P[i]);;  Collected(last);;
    P2:=List([1..Length(P)-Length(I)],i->[P1[i],P1[i+1],P1[i+2],P1[i+3],P1[i+4],P1[i+5],P1[i+6]]);;
    P3:=List(Positions(P2,I),i->P[i]); Length(P3);

Extensions

a(8)-a(24) from Giovanni Resta, Jul 25 2017
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