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 13 results. Next

A204189 Benoît Perichon's 26 primes in arithmetic progression.

Original entry on oeis.org

43142746595714191, 48425980631694091, 53709214667673991, 58992448703653891, 64275682739633791, 69558916775613691, 74842150811593591, 80125384847573491, 85408618883553391, 90691852919533291, 95975086955513191, 101258320991493091, 106541555027472991, 111824789063452891, 117108023099432791, 122391257135412691, 127674491171392591, 132957725207372491, 138240959243352391, 143524193279332291, 148807427315312191, 154090661351292091, 159373895387271991, 164657129423251891, 169940363459231791, 175223597495211691
Offset: 1

Views

Author

Jonathan Sondow, Jan 14 2012

Keywords

Comments

Longest known arithmetic progression of primes as of Jan 14, 2012.
Discovered on Apr 12 2010 by Benoît Perichon using software by Jaroslaw Wroblewski and Geoff Reynolds in a distributed PrimeGrid project.

References

  • R. K. Guy, Unsolved Problems in Number Theory, 2nd ed., Springer-Verlag, 1994, A5 and A6.
  • P. Ribenboim, The New Book of Prime Number Records, Springer-Verlag, 1989, p. 224.

Crossrefs

Programs

  • Mathematica
    a[1] := 43142746595714191; a[n_] := a[n] = a[n - 1] + 5283234035979900; Table[a[n], {n, 26}] (* Alonso del Arte, Jan 14 2012 *)
    Range[ 43142746595714191, 175223597495211691, 5283234035979900] (* Michael Somos, Jan 15 2012 *)
  • PARI
    a(n)=5283234035979900*n+37859512559734291 \\ Charles R Greathouse IV, Jan 15 2012

Formula

a(n) = 43142746595714191 + 5283234035979900*(n-1) for n = 1, 2, ..., 26.
a(n) = 43142746595714191 + 23681770*23#*(n-1) for n = 1..26, where 23# = 2*3*5*7*11*13*17*19*23 = 223092870 = A002110(9).

A261140 a(n) = 3486107472997423 + (n-1)*371891575525470.

Original entry on oeis.org

3486107472997423, 3857999048522893, 4229890624048363, 4601782199573833, 4973673775099303, 5345565350624773, 5717456926150243, 6089348501675713, 6461240077201183, 6833131652726653, 7205023228252123, 7576914803777593, 7948806379303063, 8320697954828533
Offset: 1

Views

Author

Marco Ripà, Aug 10 2015

Keywords

Comments

The terms n = 1..26 are prime. This is the longest sequence of primes in arithmetic progression with smallest end, a(26)=12783396861134173, known as of August 10, 2015.

Examples

			a(26) = 3486107472997423 + 25*371891575525470 = 12783396861134173 is prime.
		

Crossrefs

Programs

  • Magma
    [3486107472997423+(n-1)*371891575525470: n in [1..20]];
    
  • Mathematica
    Table[3486107472997423 + (n - 1) 371891575525470, {n, 1, 20}]
    LinearRecurrence[{2,-1},{3486107472997423,3857999048522893},20] (* Harvey P. Dale, May 14 2022 *)
  • PARI
    Vec(-x*(3114215897471953*x-3486107472997423)/(x-1)^2 + O(x^40)) \\ Colin Barker, Aug 25 2015

Formula

a(n) = 3486107472997423 + (n-1)*1666981*A002110(9).
G.f.: -x*(3114215897471953*x-3486107472997423) / (x-1)^2. - Colin Barker, Aug 25 2015

A033290 Ten consecutive primes in arithmetic progression.

Original entry on oeis.org

100996972469714247637786655587969840329509324689190041803603417758904341703348882159067229719, 100996972469714247637786655587969840329509324689190041803603417758904341703348882159067229929, 100996972469714247637786655587969840329509324689190041803603417758904341703348882159067230139
Offset: 0

Views

Author

Keywords

Comments

This was the first known case, found in 1998. The full 10 terms are linked below. - Jens Kruse Andersen, Jun 30 2014

Crossrefs

Formula

N*m + x + 210*b, b = 0..9.
a(n) = a(0)+210*n, and a(n+1) = nextprime(a(n)+1). - Jens Kruse Andersen, Jun 30 2014

A327760 Primes in Rob Gahan's arithmetic progression of 27 primes.

Original entry on oeis.org

224584605939537911, 242720302537486841, 260855999135435771, 278991695733384701, 297127392331333631, 315263088929282561, 333398785527231491, 351534482125180421, 369670178723129351, 387805875321078281, 405941571919027211, 424077268516976141, 442212965114925071
Offset: 1

Views

Author

Felix Fröhlich, Sep 25 2019

Keywords

Comments

This arithmetic progression of 27 primes (AP27) was discovered by Rob Gahan on 23 September 2019 as part of PrimeGrid's AP27 Search subproject (cf. Goetz, 2019).

Crossrefs

Programs

  • Mathematica
    A327760[n_] := 224584605939537911 + (n-1)*18135696597948930;
    Array[A327760, 27] (* Paolo Xausa, Jan 30 2024 *)
  • PARI
    vector(27, t, 224584605939537911+81292139*223092870*(t-1))

A363980 Tom Greer's arithmetic progression of 27 primes.

Original entry on oeis.org

277699295941594831, 315809464967513821, 353919633993432811, 392029803019351801, 430139972045270791, 468250141071189781, 506360310097108771, 544470479123027761, 582580648148946751, 620690817174865741, 658800986200784731, 696911155226703721, 735021324252622711
Offset: 1

Views

Author

Marco Ripà, Jun 30 2023

Keywords

Comments

At the time of submission (June 2023), this sequence is the arithmetic progression of 27 primes having the largest known initial and final term and it was found by Tom Greer on 26 May 2023 as part of PrimeGrid's AP27, running the program AP26 (this is the second known AP27 to date, see A327760).

Examples

			a(3) = 277699295941594831 + 2*170826477*223092870 is prime.
		

Crossrefs

Programs

  • Mathematica
    A363980[n_]:=277699295941594831 + (n-1)*38110169025918990;
    Array[A363980, 27] (* Paolo Xausa, Jan 30 2024 *)
  • PARI
    vector(27, t, 277699295941594831+170826477*223092870*(t-1))

Formula

a(n+1) = 277699295941594831 + n*170826477*223092870, for n = 0, 1, ..., 26.

A374949 Michael Kwok's arithmetic progression of 27 primes.

Original entry on oeis.org

605185576317848261, 639847242910261121, 674508909502673981, 709170576095086841, 743832242687499701, 778493909279912561, 813155575872325421, 847817242464738281, 882478909057151141, 917140575649564001, 951802242241976861, 986463908834389721, 1021125575426802581
Offset: 1

Views

Author

Marco Ripà, Jul 24 2024

Keywords

Comments

At the time of submission (July 2024), this sequence is the arithmetic progression of 27 primes having the largest known initial and final term and it was found by Michael Kwok on 10 December 2023 as part of the project PrimeGrid, running the program AP26 (this is the third known AP27 to date, see A327760 and A363980).

Examples

			a(3) = 605185576317848261 + 2*34661666592412860 is prime.
		

Crossrefs

Programs

  • Mathematica
    A374949[n_]:=605185576317848261 + (n-1)* 34661666592412860; Array[A374949, 27]
  • PARI
    vector(27, t, 605185576317848261+155368778*223092870*(t-1))

Formula

a(n+1) = 605185576317848261 + n*34661666592412860, for n = 0, 1, ..., 26.

A317163 a(n) = 48277590120607451 + (n-1)*8440735245322380.

Original entry on oeis.org

48277590120607451, 56718325365929831, 65159060611252211, 73599795856574591, 82040531101896971, 90481266347219351, 98922001592541731, 107362736837864111, 115803472083186491, 124244207328508871, 132684942573831251, 141125677819153631, 149566413064476011
Offset: 1

Views

Author

Marco Ripà, Jul 23 2018

Keywords

Comments

a(1), a(2), ..., a(26) are prime. As of Jul 23 2018, this is one of the longest known sequences of primes in arithmetic progression, and was found by Bruce E. Slade in 2017.

Examples

			a(26) = 48277590120607451 + 25*37835074*223092870 = 259295971253666951 is prime.
		

Crossrefs

Programs

  • GAP
    List([1..26],n->55837783597462913+(n-1)*13858932213216090); # Marco Ripà, Aug 10 2018
  • Maple
    seq(48277590120607451+(n-1)*8440735245322380,n=1..26); # Marco Ripà, Aug 10 2018
  • Mathematica
    Table[48277590120607451 + (n - 1) 8440735245322380, {n, 1, 26}]

Formula

a(n) = 48277590120607451 + a(n-1)*37835074*23#, where 23# := 2*3*5*7*11*13*17*19*23 = 223092870.

A317164 a(n) = 55837783597462913 + (n-1)*13858932213216090.

Original entry on oeis.org

55837783597462913, 69696715810679003, 83555648023895093, 97414580237111183, 111273512450327273, 125132444663543363, 138991376876759453, 152850309089975543, 166709241303191633, 180568173516407723, 194427105729623813, 208286037942839903, 222144970156055993
Offset: 1

Views

Author

Marco Ripà, Jul 23 2018

Keywords

Comments

The terms for n = 1..26 are prime. As of Jul 23 2018, this is one of the longest known sequences of primes in arithmetic progression.

Examples

			a(26) = 55837783597462913 + 25*62121807*223092870 = 402311088927865163 is prime.
		

Crossrefs

Programs

  • GAP
    List([1..25],n->55837783597462913+(n-1)*13858932213216090); # Muniru A Asiru, Jul 24 2018
  • Maple
    seq(55837783597462913+(n-1)*13858932213216090,n=1..15); # Muniru A Asiru, Jul 24 2018
  • Mathematica
    Table[55837783597462913 + (n - 1) 13858932213216090, {n, 1, 25}]

Formula

a(n) = 455837783597462913 + a(n-1)*62121807*23#, where 23# := 2*3*5*7*11*13*17*19*23 = 223092870.

A260939 Thirteen primes in arithmetic progression with difference 60060 and minimal initial term.

Original entry on oeis.org

4943, 65003, 125063, 185123, 245183, 305243, 365303, 425363, 485423, 545483, 605543, 665603, 725663
Offset: 1

Views

Author

Marco Ripà, Aug 05 2015

Keywords

Comments

This sequence is 13 primes long and was discovered by W. N. Seredinsky.

Examples

			a(4) = 4943 + 3*60060 = 185123.
		

Crossrefs

Programs

Formula

a(n) = 4943 + (n-1)*60060 = 4943 + (n-1)*2*A002110(6).

A261152 a(n) = 161004359399459161 + (n-1)*10644900609172830.

Original entry on oeis.org

161004359399459161, 171649260008631991, 182294160617804821, 192939061226977651, 203583961836150481, 214228862445323311, 224873763054496141, 235518663663668971, 246163564272841801, 256808464882014631, 267453365491187461, 278098266100360291, 288743166709533121
Offset: 1

Views

Author

Marco Ripà, Aug 10 2015

Keywords

Comments

The terms n = 1..26 are prime. This is the longest and largest sequence of primes in arithmetic progression, a(26)=427126874628779911, known as of August 10, 2015.

Examples

			a(26) = 161004359399459161 + 25*10644900609172830 = 427126874628779911 is prime.
		

Crossrefs

Programs

  • Magma
    [161004359399459161+(n-1)*10644900609172830: n in [1..20]]; // Bruno Berselli, Aug 23 2015
  • Mathematica
    Table[161004359399459161 + (n - 1) 10644900609172830, {n, 1, 20}] (* Bruno Berselli, Aug 23 2015 *)

Formula

a(n) = 161004359399459161 + (n-1)*47715109*A002110(9).
G.f.: x*(161004359399459161 - 150359458790286331*x)/(1 - x)^2. [Bruno Berselli, Aug 23 2015]
Showing 1-10 of 13 results. Next