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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A136060 Daughter primes of order 11.

Original entry on oeis.org

3, 7, 13, 31, 37, 43, 61, 73, 103, 163, 211, 223, 241, 271, 307, 313, 331, 367, 397, 421, 463, 523, 541, 577, 643, 727, 757, 853, 877, 883, 937, 1051, 1087, 1093, 1153, 1237, 1291, 1303, 1381, 1423, 1471, 1597, 1693, 1723, 1777, 1951, 1993, 2131, 2161, 2203
Offset: 1

Views

Author

Artur Jasinski, Dec 12 2007

Keywords

Comments

For smallest daughter primes of order n see A136019 (also definition). For daughter primes of order 1 see A088878. For daughter primes of order 2 see A136051. For daughter primes of order 3 see A136052. For daughter primes of order 4 see A136053. For daughter primes of order 5 see A136054. For daughter primes of order 6 see A136055. For daughter primes of order 7 see A136056. For daughter primes of order 8 see A136057. For daughter primes of order 9 see A136058. For daughter primes of order 10 see A136059.

Crossrefs

Programs

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

Crossrefs

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.

Crossrefs

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.

Crossrefs

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.

Crossrefs

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.

Crossrefs

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.

Crossrefs

Programs

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

A259730 Primes p such that both 2*p - 3 and 3*p - 2 are prime.

Original entry on oeis.org

3, 5, 7, 11, 13, 23, 37, 43, 53, 67, 71, 113, 127, 137, 167, 181, 191, 193, 211, 251, 263, 331, 347, 373, 431, 433, 443, 461, 487, 587, 727, 751, 757, 907, 991, 1021, 1091, 1103, 1171, 1187, 1213, 1231, 1297, 1367, 1453, 1483, 1597, 1637, 1663, 1667, 1733
Offset: 1

Views

Author

Reinhard Zumkeller, Jul 05 2015

Keywords

Comments

A010051(2*a(n) - 3) * A010051(3*a(n) - 2) = 1;
A259758(n) = (2*a(n) - 3) * (3*a(n) - 2).
Except for a(1)=3 this is the same sequence as primes p such that A288814(3*p) - A288814(2*p) = 5. - David James Sycamore, Jul 22 2017
Furthermore, (A288814(3*p)*A288814(2*p))/6 belongs to A259758. - David James Sycamore, Jul 23 2017

Crossrefs

Intersection of A063908 and A088878; A172287, A259758.

Programs

  • Haskell
    import Data.List.Ordered (isect)
    a259730 n = a259730_list !! (n-1)
    a259730_list = a063908_list `isect` a088878_list
    
  • Mathematica
    Select[Prime@ Range@ 270, Times @@ Boole@ Map[PrimeQ, {2 # - 3, 3 # - 2}] > 0 &] (* Michael De Vlieger, Jul 22 2017 *)
    Select[Prime[Range[300]],AllTrue[{2#-3,3#-2},PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 08 2020 *)
  • PARI
    lista(nn) = forprime(p=3, nn, if(isprime(2*p-3) && isprime(3*p-2), print1(p, ", "))); \\ Altug Alkan, Jul 22 2017

A172287 Primes p such that exactly one of 2p-3 and 3p-2 is prime.

Original entry on oeis.org

17, 31, 41, 47, 61, 83, 97, 101, 103, 107, 157, 163, 223, 233, 241, 257, 271, 277, 283, 293, 307, 311, 313, 317, 337, 401, 421, 457, 467, 491, 521, 523, 541, 547, 557, 563, 577, 593, 601, 613, 617, 631, 641, 643, 647, 653, 661, 673, 677, 701, 743, 761, 773
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Jan 30 2010

Keywords

Comments

A010051(2*a(n)+3) + A010051(3*a(n)+2) = 1; each term is either a term of A063908 or of A088878. - Reinhard Zumkeller, Jul 02 2015
No terms end in 9. Dickson's conjecture implies that there are infinitely many terms. - Robert Israel, Jul 02 2015

Examples

			a(1)=17 because 2*17-3=31 is prime and 3*17-2=49 is nonprime.
19 is not a term because neither 2*19-3=35 nor 3*19-2=55 is prime;
23 is not a term because both 2*23-3=43 and 3*23-2=67 are prime.
		

Crossrefs

Programs

  • Haskell
    a172287 n = a172287_list !! (n-1)
    a172287_list = filter
       (\p -> a010051' (2 * p - 3) + a010051' (3 * p - 2) == 1) a000040_list
    -- Reinhard Zumkeller, Jul 02 2015
  • Maple
    A172287:=n->`if`(isprime(n) and (isprime(2*n-3) xor isprime(3*n-2)), n, NULL): seq(A172287(n), n=1..1000); # Wesley Ivan Hurt, Jun 23 2015
  • Mathematica
    Select[Prime@ Range@ 150, Xor[PrimeQ[2 # - 3], PrimeQ[3 # - 2]] &] (* Michael De Vlieger, Jul 01 2015 *)

Extensions

Extended by Charles R Greathouse IV, Mar 25 2010

A153184 Numbers n such that 3*n-2 is not prime.

Original entry on oeis.org

1, 2, 4, 6, 8, 9, 10, 12, 14, 16, 17, 18, 19, 20, 22, 24, 26, 28, 29, 30, 31, 32, 34, 36, 38, 39, 40, 41, 42, 44, 45, 46, 48, 49, 50, 52, 54, 56, 57, 58, 59, 60, 62, 63, 64, 66, 68, 69, 70, 72, 73, 74, 76, 78, 79, 80, 82, 83, 84, 85, 86, 87, 88, 89, 90, 92, 94, 96, 97, 98, 99, 100
Offset: 1

Views

Author

Vincenzo Librandi, Dec 20 2008

Keywords

Comments

One more than the associated value in A153309. - R. J. Mathar, Jan 05 2011

Examples

			Distribution of the odd terms > a(1) in the following triangular array:
*;
*,9;
*,*,17;
*,*,*,*;
*,19,*,*,41;
*,*,31,*,*,57;
*,*,*,*,*,*,*;
*,29,*,*,63,*,*,97;
*,*,45,*,*,83,*,*,121;
*,*, *,*,*,*, *,*, *, *;
*,39,*,*,85,*,*,131,*,*,177;
*,*,59,*,*,109,*,*,159,*,*,209; etc.
where * marks the non-integer values of (4*h*k + 2*k + 2*h + 3)/3 with h >= k >= 1. - _Vincenzo Librandi_, Jan 17 2013
		

Crossrefs

Programs

Formula

a(n) ~ n. - Charles R Greathouse IV, Oct 26 2015

Extensions

Erroneous comment deleted by N. J. A. Sloane, Jun 23 2010
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