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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A049203 Primes for which A049076(p) >= 5.

Original entry on oeis.org

31, 127, 709, 1787, 5381, 8527, 15299, 19577, 27457, 42043, 52711, 72727, 87803, 96797, 112129, 137077, 167449, 173867, 219613, 239489, 250751, 285191, 318211, 352007, 401519, 443419, 464939, 490643, 506683, 527623, 648391, 683873, 718807
Offset: 1

Views

Author

Neil Fernandez

Keywords

Comments

Union of A049081, A058322, A058324-A058328, A093046, etc. - R. J. Mathar, Jul 07 2012

Links

Crossrefs

Cf. A000040, A006450, A038580, A049076, A049090, A049202, A057847, A057849, A057850, A057851, A058332, A093047.

Programs

  • Maple
    map(ithprime@@4, select(isprime, [$1..137])); # Peter Luschny, Feb 17 2014
  • Mathematica
    Nest[ Prime, Range[35], 5] (* Robert G. Wilson v, Mar 15 2004 *)
  • PARI
    list(lim)=my(v=List(),q,r,s,t); forprime(p=2,lim, if(isprime(q++) && isprime(r++) && isprime(s++) && isprime(t++), listput(v,p))); Vec(v) \\ Charles R Greathouse IV, Feb 16 2017

Formula

a(n) = A000040(A049090(n)). - R. J. Mathar, Jul 07 2012
a(n) ~ n (log n)^5. - Charles R Greathouse IV, Feb 16 2017

Extensions

More terms from Robert G. Wilson v, Nov 10 2000
Name corrected by Sean A. Irvine, Jul 21 2021

A058324 Primes for which A049076(p) = 8.

Original entry on oeis.org

709, 167449, 1128889, 3042161, 4535189, 7474967, 14161729, 19734581, 23391799, 29499439, 38790341, 56011909, 59053067, 68425619, 87019979, 101146501, 113256643, 119535373, 127065427, 138034009, 185350441, 196100297, 207460717, 233784751, 241568891, 280256489
Offset: 1

Views

Author

Robert G. Wilson v, Dec 12 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058325, A058326, A058327, A058328, A093046, A006450.

Programs

  • Maple
    map(ithprime@@7, remove(isprime, [$1..38]))[];  # Alois P. Heinz, Mar 15 2020
  • Mathematica
    Nest[ Prime, Select[ Range[34], !PrimeQ[ # ] &], 7] (* Robert G. Wilson v, Mar 15 2004 *)

Formula

a(n) = A000040(A058322(n)). - R. J. Mathar, Jul 07 2012

Extensions

More terms from Alois P. Heinz, Mar 15 2020

A058328 Primes for which A049076(p) = 12.

Original entry on oeis.org

9737333, 16123689073, 175650481151, 592821132889, 963726515729, 1765037224331, 3809491708961, 5669795882633, 6947574946087, 9163611272327, 12695664159413, 19638537755027, 20909033866927, 24894639811901
Offset: 1

Views

Author

Robert G. Wilson v, Dec 12 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058324, A058325, A058326, A058327, A093046, A006450.

Programs

  • Mathematica
    Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 11] (* Robert G. Wilson v, Mar 15 2004 *)

Formula

a(n) = A000040(A058327(n)). - R. J. Mathar, Jul 07 2012

A093046 Primes for which A049076(p) = 13.

Original entry on oeis.org

174440041, 414507281407, 4952019383323, 17461204521323, 28871271685163, 53982894593057, 119543903707171, 180252380737439, 222334565193649, 295872998567819, 414190707114539, 649544694886663, 692919372869953, 829484152743469, 1111923751842437, 1335294947809661, 1532021237514419, 1635795965187779
Offset: 1

Views

Author

Robert G. Wilson v, Mar 15 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058324, A058325, A058326, A058327, A058328, A006450.

Programs

  • Mathematica
    Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 12]

Formula

a(n) = A000040(A058328(n)). - R. J. Mathar, Jul 07 2012

Extensions

a(7)-a(9) from Robert G. Wilson v, Dec 27 2005
a(10)-a(18) from Robert G. Wilson v, Mar 08 2017 using Kim Walisch's primecount.

A058325 Primes for which A049076(p) = 9.

Original entry on oeis.org

5381, 2269733, 17624813, 50728129, 77557187, 131807699, 259336153, 368345293, 440817757, 563167303, 751783477, 1107276647, 1170710369, 1367161723, 1760768239, 2062666783, 2323114841, 2458721501, 2621760397, 2860139341
Offset: 1

Views

Author

Robert G. Wilson v, Dec 12 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058324, A058326, A058327, A058328, A093046, A006450.

Programs

  • Mathematica
    Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 8] (* Robert G. Wilson v, Mar 15 2004 *)

Formula

a(n) = A000040(A058324(n)). - R. J. Mathar, Jul 07 2012

A058326 Primes for which A049076(p) = 10.

Original entry on oeis.org

52711, 37139213, 326851121, 997525853, 1559861749, 2724711961, 5545806481, 8012791231, 9672485827, 12501968177, 16917026909, 25366202179, 26887732891, 31621854169, 41192432219, 48596930311, 55022031709, 58379844161
Offset: 1

Views

Author

Robert G. Wilson v, Dec 12 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058324, A058325, A058327, A058328, A093046, A006450.

Programs

  • Mathematica
    Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 9] (* Robert G. Wilson v, Mar 15 2004 *)

Formula

a(n) = A000040(A058325(n)). - R. J. Mathar, Jul 07 2012

A058327 Primes for which A049076(p) = 11.

Original entry on oeis.org

648391, 718064159, 7069067389, 22742734291, 36294260117, 64988430769, 136395369829, 200147986693, 243504973489, 318083817907, 435748987787, 664090238153, 705555301183, 835122557939, 1099216100167, 1305164025929
Offset: 1

Views

Author

Robert G. Wilson v, Dec 12 2000

Keywords

Links

Crossrefs

Cf. A049076, A007821, A049078, A049079, A049080, A049081, A058322, A058324, A058325, A058326, A058328, A093046, A006450.

Programs

  • Mathematica
    Nest[ Prime, Select[ Range[30], !PrimeQ[ # ] &], 10] (* Robert G. Wilson v, Mar 15 2004 *)

Formula

a(n) = A000040(A058326(n)). - R. J. Mathar, Jul 07 2012

A050439 Fifth-order composites.

Original entry on oeis.org

39, 49, 55, 56, 60, 69, 74, 77, 78, 84, 93, 94, 95, 100, 105, 106, 110, 115, 119, 124, 125, 126, 130, 133, 140, 141, 145, 152, 155, 156, 159, 162, 164, 165, 170, 174, 180, 183, 184, 188, 189, 198, 201, 202, 203, 206, 207, 209, 212, 213, 218, 222, 225, 231
Offset: 1

Views

Author

Michael Lugo (mlugo(AT)thelabelguy.com), Dec 22 1999

Keywords

Examples

			C(C(C(C(C(8))))) = C(C(C(C(15)))) = C(C(C(25))) = C(C(38)) = C(55) = 77. So 77 is in the sequence.

Links

Crossrefs

Cf. A049076-A049081, A006450, A050435, A050436, A050438, A050440.

Programs

  • Maple
    C := remove(isprime,[$4..1000]): seq(C[C[C[C[C[n]]]]],n=1..100);

Formula

Let C(n) be the n-th composite number, with C(1)=4. Then these are numbers C(C(C(C(C(n))))).

Extensions

More terms from Asher Auel Dec 15 2000

A050436 Third-order composites.

Original entry on oeis.org

16, 21, 25, 26, 28, 33, 36, 38, 39, 42, 48, 49, 50, 52, 55, 56, 57, 60, 64, 68, 69, 70, 72, 74, 77, 78, 80, 84, 87, 88, 90, 93, 94, 95, 98, 100, 104, 105, 106, 110, 111, 115, 117, 118, 119, 121, 122, 124, 125, 126, 130, 133, 135, 138, 140, 141, 145, 146, 147
Offset: 1

Views

Author

Michael Lugo (mlugo(AT)thelabelguy.com), Dec 22 1999

Keywords

Examples

			C(C(C(8))) = C(C(15)) = C(25) = 38. So 38 is in the sequence.

Links

Crossrefs

Cf. A049076, A049077, A049078, A049079, A049080, A049081, A006450, A050435, A050438, ...

Programs

  • Maple
    C := remove(isprime,[$4..1000]): seq(C[C[C[C[n]]]],n=1..100);
  • Mathematica
    Nest[Values@ KeySelect[MapIndexed[First@ #2 -> #1 &, #], CompositeQ] &, Select[Range@ 150, CompositeQ], 2] (* Michael De Vlieger, Jul 22 2017 *)

Formula

Let C(n) be the n-th composite number, with C(1)=4. Then these are numbers C(C(C(n))).

Extensions

More terms from Asher Auel Dec 15 2000

A050438 Fourth-order composites.

Original entry on oeis.org

26, 33, 38, 39, 42, 49, 52, 55, 56, 60, 68, 69, 70, 74, 77, 78, 80, 84, 88, 93, 94, 95, 98, 100, 105, 106, 110, 115, 118, 119, 121, 124, 125, 126, 130, 133, 138, 140, 141, 145, 146, 152, 154, 155, 156, 159, 160, 162, 164, 165, 170, 174, 176, 180, 183, 184
Offset: 1

Views

Author

Michael Lugo (mlugo(AT)thelabelguy.com), Dec 22 1999

Keywords

Examples

			C(C(C(C(8)))) = C(C(C(15))) = C(C(25)) = C(38) = 55. So 55 is in the sequence.

Links

Crossrefs

Cf. A049076-A049081, A006450, A050435, A050436, A050439, A050440.

Programs

  • Maple
    C := remove(isprime,[$4..1000]): seq(C[C[C[C[n]]]],n=1..100);

Formula

Let C(n) be the n-th composite number, with C(1)=4. Then these are numbers C(C(C(C(n)))).

Extensions

More terms from Asher Auel Dec 15 2000
Previous Showing 11-20 of 29 results. Next

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