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 11 results. Next

A136061 Primes p such that (p+4)/5 is also prime.

Original entry on oeis.org

11, 31, 61, 151, 181, 211, 331, 541, 631, 691, 751, 811, 991, 1051, 1201, 1381, 1531, 1741, 1831, 1861, 2161, 2281, 2311, 2731, 2851, 3001, 3061, 3301, 3361, 3541, 3631, 3691, 3931, 4051, 4111, 4261, 4591, 4831, 4951, 5101, 5431, 5581, 5641, 5851, 6151
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

Equivalently: Mother primes of order 2. For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136062, A136063, A136064, A136065, A136066, A136067, A136068, A136069, A136070.

Programs

  • GAP
    A136061:=Filtered(Filtered([1..10^6],IsPrime),p->IsPrime((p+4)/5)); # Muniru A Asiru, Oct 10 2017
  • Mathematica
    n = 2; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a
Select[Prime[Range[400]], PrimeQ[(# + 4) / 5]&] (* Vincenzo Librandi, Apr 14 2013 *)
  • PARI
    {forprime(p=1,1e4/*default(primelimit)*/, p%5-1 & next; isprime(p\5+1) & print1(p","))}  \\ M. F. Hasler, Feb 26 2012

A136062 Mother primes of order 3.

Original entry on oeis.org

29, 43, 71, 113, 127, 197, 211, 281, 421, 463, 491, 547, 617, 673, 701, 743, 757, 883, 911, 953, 967, 1051, 1093, 1163, 1373, 1471, 1583, 1597, 1667, 1877, 1933, 2143, 2213, 2311, 2423, 2437, 2647, 2801, 2857, 2927, 3011, 3067, 3137, 3221, 3347, 3557
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136063, A136064, A136065, A136066, A136067, A136068, A136069, A136070.

Programs

  • Mathematica
    n = 3; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136069 Mother primes of order 10.

Original entry on oeis.org

43, 127, 211, 337, 379, 463, 631, 757, 883, 967, 1093, 1471, 1723, 2017, 2143, 2269, 2647, 2731, 2857, 3109, 3613, 3739, 4159, 4663, 4789, 4999, 5503, 5881, 5923, 6133, 6427, 6553, 6637, 7057, 7309, 7393, 7687, 8317, 8779, 8821, 9199, 9283, 9661, 9787
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063. For mother primes of order 5 see A136064. For mother primes of order 6 see A136065. For mother primes of order 8 see A136066. For mother primes of order 9 see A136067.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136064, A136065, A136066, A136067, A136068, A136070.

Programs

  • Mathematica
    n = 10; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136063 Mother primes of order 4.

Original entry on oeis.org

19, 37, 109, 163, 199, 271, 379, 523, 541, 631, 739, 919, 1009, 1171, 1459, 1549, 1621, 1783, 1999, 2053, 2089, 2143, 2161, 2251, 2521, 2539, 2791, 2971, 3169, 3673, 3889, 3943, 4159, 4483, 4519, 4861, 5059, 5113, 5563, 5779, 5869, 5923, 6211, 6301, 6373
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136064, A136065, A136066, A136067, A136068, A136069, A136070.

Programs

  • Mathematica
    n = 4; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136064 Mother primes of order 5.

Original entry on oeis.org

23, 67, 199, 331, 397, 463, 661, 727, 859, 1123, 1783, 2113, 2179, 2311, 2971, 3037, 3433, 3631, 3697, 4027, 4093, 4159, 4357, 4621, 5347, 5479, 5743, 6007, 6271, 6337, 6733, 7393, 7591, 7789, 8053, 8317, 8647, 9043, 9109, 9439, 9967, 10099, 10627
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136065, A136066, A136067, A136068, A136069, A136070.

Programs

  • Mathematica
    n = 5; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136065 Mother primes of order 6.

Original entry on oeis.org

53, 79, 131, 157, 521, 547, 599, 677, 859, 911, 937, 1249, 1301, 1327, 1951, 2029, 2237, 2341, 2549, 2731, 2887, 2939, 3121, 3251, 3329, 3407, 3511, 3797, 4057, 4759, 4967, 5591, 5981, 6007, 6761, 7229, 7307, 7411, 7489, 7879, 8009, 8191, 8581, 8737
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063. For mother primes of order 5 see A136064.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136064, A136066, A136067, A136068, A136069, A136070.

Programs

  • Mathematica
    n = 6; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136067 Mother primes of order 8.

Original entry on oeis.org

103, 307, 613, 1021, 1123, 1327, 2143, 2347, 2551, 3061, 3571, 3877, 4591, 6427, 6733, 7753, 8263, 8467, 9181, 9283, 10303, 10711, 11731, 12037, 12343, 12547, 12853, 15607, 15913, 16831, 17137, 17341, 17851, 18973, 19891, 21013, 21727
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063. For mother primes of order 5 see A136064. For mother primes of order 6 see A136065. For mother primes of order 8 see A136066.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136064, A136065, A136066, A136068, A136069, A136070.

Programs

  • Mathematica
    n = 8; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136068 Mother primes of order 9.

Original entry on oeis.org

191, 229, 419, 571, 761, 1103, 1483, 1559, 1901, 2053, 2129, 2851, 3079, 4219, 4409, 4523, 4561, 4751, 6271, 6689, 6803, 7069, 7753, 8171, 8209, 8513, 8741, 8779, 9311, 9463, 9539, 10831, 11743, 11971, 12161, 12503, 12541, 12959, 14251, 14593, 14669
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063. For mother primes of order 5 see A136064. For mother primes of order 6 see A136065. For mother primes of order 8 see A136066. For mother primes of order 9 see A136067.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136064, A136065, A136066, A136067, A136069, A136070.

Programs

  • Mathematica
    n = 9; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A136070 Mother primes of order 11.

Original entry on oeis.org

47, 139, 277, 691, 829, 967, 1381, 1657, 2347, 3727, 4831, 5107, 5521, 6211, 7039, 7177, 7591, 8419, 9109, 9661, 10627, 12007, 12421, 13249, 14767, 16699, 17389, 19597, 20149, 20287, 21529, 24151, 24979, 25117, 26497, 28429, 29671, 29947
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest mother primes of order n see A136020 (also definition). For mother primes of order 1 see A091180. For mother primes of order 2 see A136061. For mother primes of order 3 see A136062. For mother primes of order 4 see A136063. For mother primes of order 5 see A136064. For mother primes of order 6 see A136065. For mother primes of order 8 see A136066. For mother primes of order 9 see A136067. For mother primes of order 10 see A136068.

Links

Crossrefs

Cf. A088878, A091180, A136019, A136020, A136061, A136062, A136063, A136064, A136065, A136066, A136067, A136068, A136069.

Programs

  • Mathematica
    n = 11; a = {}; Do[If[PrimeQ[(Prime[k] + 2n)/(2n + 1)], AppendTo[a, Prime[k]]], {k, 1, 1500}]; a

A140378 Lengths of runs of consecutive primes and nonprimes in A007775.

Original entry on oeis.org

1, 12, 1, 6, 1, 3, 1, 6, 2, 2, 1, 2, 1, 3, 1, 2, 1, 3, 1, 4, 2, 1, 2, 6, 1, 1, 1, 1, 1, 6, 2, 1, 2, 4, 3, 2, 2, 4, 1, 1, 1, 1, 1, 3, 1, 2, 2, 1, 1, 2, 1, 2, 1, 3, 1, 4, 2, 1, 1, 2, 2, 3, 2, 2, 4, 2, 2, 1, 1, 4, 2, 1, 1, 4, 1, 3, 2, 1, 1, 3, 1, 3, 2, 2, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 3, 2, 2, 2
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Jun 13 2008

Keywords

Comments

Primes can be classified according to their remainder modulo 30: remainder 1 (A136066), 7 (A132231), 11 (A132232), 13 (A132233), 17 (A039949), 19 (A132234), 23 (A132235), or 29 (A132236). In the sequence A007775 of all numbers (prime or nonprime) in any of these remainder classes, we look for runs of numbers that are successively prime or nonprime and place the lengths of these runs in this sequence.

Examples

			Groups of runs in A007775 are (1), (7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47), (49), (53, 59, 61, 67, 71, 73), (77), (79, 83,...), which is 1 nonprime followed by 12 primes followed by 1 nonprime followed by 6 primes etc.

Crossrefs

Cf. A136066, A132231, A132232, A132233, A039919, A132234, A132235, A132236.

Programs

  • Maple
    A007775 := proc(n) option remember ; local a; if n = 1 then 1; else for a from A007775(n-1)+1 do if a mod 2 <>0 and a mod 3 <>0 and a mod 5 <> 0 then RETURN(a) ; fi ; od: fi ; end: A := proc() local al,isp,n; al := 0: isp := false ; n := 1: while n< 300 do a := A007775(n) ; if isprime(a) <> isp then printf("%d,",al) ; al := 1; isp := not isp ; else al := al+1 ; fi ; n := n+1: od: end: A() ; # R. J. Mathar, Jun 16 2008

Extensions

Edited by R. J. Mathar, Jun 16 2008
Showing 1-10 of 11 results. Next

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