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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A156323 List of prime pairs of the form (p, p+12).

Original entry on oeis.org

5, 17, 7, 19, 11, 23, 17, 29, 19, 31, 29, 41, 31, 43, 41, 53, 47, 59, 59, 71, 61, 73, 67, 79, 71, 83, 89, 101, 97, 109, 101, 113, 127, 139, 137, 149, 139, 151, 151, 163, 167, 179, 179, 191, 181, 193, 199, 211, 211, 223, 227, 239, 229, 241, 239, 251, 251, 263, 257
Offset: 1

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Author

Vincenzo Librandi, Feb 08 2009

Keywords

Examples

			For p=5, 5+12=17, (5,17); p=59, 59+12=71, (59,71)
		

Crossrefs

Programs

  • Mathematica
    Flatten[Select[{#,#+12}&/@Prime[Range[100]], PrimeQ[Last[#]]&]]  (* Harvey P. Dale, Mar 23 2011 *)

A164566 Primes p such that 7*p-6 and 7*p+6 are also prime numbers.

Original entry on oeis.org

5, 11, 19, 31, 41, 61, 71, 109, 151, 211, 229, 269, 379, 419, 431, 439, 479, 619, 641, 709, 739, 809, 839, 971, 1009, 1069, 1229, 1259, 1319, 1361, 1439, 1451, 1499, 1531, 1579, 1669, 1801, 1879, 1889, 2011, 2111, 2239, 2269, 2381, 2411, 2551, 2579, 2591
Offset: 1

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Author

Keywords

Comments

Primes of the form A087681(k)/7, any index k.

Examples

			For p=5, both 7*5-6=29 and 7*5+6=41 are prime,
for p=11, both 7*11-6=71 and 7*11+6=83 are prime.
		

Crossrefs

Programs

  • Magma
    [p: p in PrimesUpTo(3000) | IsPrime(7*p-6) and IsPrime(7*p+6)]; // Vincenzo Librandi, Apr 09 2013
    
  • Mathematica
    lst={};Do[p=Prime[n];If[PrimeQ[7*p-6]&&PrimeQ[7*p+6],AppendTo[lst,p]], {n,6!}];lst
    Select[Prime[Range[700]], And @@ PrimeQ/@{7 # + 6, 7 # - 6}&] (* Vincenzo Librandi, Apr 09 2013 *)
  • PARI
    is(n)=isprime(n) && isprime(7*n-6) && isprime(7*n+6) \\ Charles R Greathouse IV, Mar 28 2017

Formula

A136052 INTERSECT A023225. [R. J. Mathar, Aug 20 2009]

Extensions

Examples rephrased by R. J. Mathar, Aug 20 2009

A231608 Table whose n-th row consists of primes p such that p + 2n is also prime, read by antidiagonals.

Original entry on oeis.org

3, 3, 5, 5, 7, 11, 3, 7, 13, 17, 3, 5, 11, 19, 29, 5, 7, 11, 13, 37, 41, 3, 7, 13, 23, 17, 43, 59, 3, 5, 11, 19, 29, 23, 67, 71, 5, 7, 17, 17, 31, 53, 31, 79, 101, 3, 11, 13, 23, 19, 37, 59, 37, 97, 107, 7, 11, 13, 31, 29, 29, 43, 71, 41, 103, 137
Offset: 1

Views

Author

T. D. Noe, Nov 26 2013

Keywords

Examples

			The following sequences are read by antidiagonals
{3, 5, 11, 17, 29, 41, 59, 71, 101, 107,...}
{3, 7, 13, 19, 37, 43, 67, 79, 97, 103,...}
{5, 7, 11, 13, 17, 23, 31, 37, 41, 47,...}
{3, 5, 11, 23, 29, 53, 59, 71, 89, 101,...}
{3, 7, 13, 19, 31, 37, 43, 61, 73, 79,...}
{5, 7, 11, 17, 19, 29, 31, 41, 47, 59,...}
{3, 5, 17, 23, 29, 47, 53, 59, 83, 89,...}
{3, 7, 13, 31, 37, 43, 67, 73, 97, 151,...}
{5, 11, 13, 19, 23, 29, 41, 43, 53, 61,...}
{3, 11, 17, 23, 41, 47, 53, 59, 83, 89,...}
...
		

Crossrefs

Cf. A020483 (numbers in first column).
Cf. A086505 (numbers on the diagonal).

Programs

  • Maple
    A231608 := proc(n,k)
        local j,p ;
        j := 0 ;
        p := 2;
        while j < k do
            if isprime(p+2*n ) then
                j := j+1 ;
            end if;
            if j = k then
                return p;
            end if;
            p := nextprime(p) ;
        end do:
    end proc:
    for n from 1 to 10 do
        for k from 1 to 10 do
            printf("%3d ",A231608(n,k)) ;
        end do;
        printf("\n") ;
    end do: # R. J. Mathar, Nov 19 2014
  • Mathematica
    nn = 10; t = Table[Select[Range[100*nn], PrimeQ[#] && PrimeQ[# + 2*n] &, nn], {n, nn}]; Table[t[[n-j+1, j]], {n, nn}, {j, n}]

A046137 Primes p such that p+4 and p+12 are also prime.

Original entry on oeis.org

7, 19, 67, 97, 127, 229, 397, 487, 739, 757, 907, 1009, 1279, 1447, 1567, 1597, 1609, 1867, 1999, 2239, 2269, 2377, 2539, 2659, 2707, 3037, 3217, 3319, 3457, 3529, 3697, 3877, 3907, 3919, 4639, 4789, 4999, 5167, 5437, 5569, 5647, 5689, 5737
Offset: 1

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Author

Keywords

Comments

All terms == 1 (mod 6). - Robert Israel, Jul 24 2015

Programs

  • Maple
    select(t -> isprime(t) and isprime(t+4) and isprime(t+12), [6*i+1 $ i=1..1000]); # Robert Israel, Jul 24 2015
  • Mathematica
    Select[Range@ 5760, AllTrue[{#, # + 4, # + 12}, PrimeQ] &] (* Michael De Vlieger, Jul 24 2015, Version 10 *)
    Select[Prime[Range[800]],AllTrue[#+{4,12},PrimeQ]&] (* Harvey P. Dale, Apr 18 2022 *)
  • PARI
    lista(nn) = forprime(p=2, nn, if (isprime(p+4) && isprime(p+12), print1(p, ", "))); \\ Michel Marcus, Jul 24 2015

Formula

A023200 INTERSECT A046133. - R. J. Mathar, Jan 23 2009

A046135 Primes p such that p+2 and p+12 are primes.

Original entry on oeis.org

5, 11, 17, 29, 41, 59, 71, 101, 137, 179, 227, 239, 269, 281, 347, 419, 431, 641, 809, 827, 1019, 1049, 1091, 1151, 1277, 1289, 1427, 1481, 1487, 1607, 1697, 1721, 1877, 2027, 2087, 2129, 2141, 2339, 2381, 2687, 2729, 2789, 2999, 3359, 3527, 3581
Offset: 1

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Author

Keywords

Comments

From Jonathan Vos Post, May 17 2006: (Start)
Could be defined as "Numbers n such that k^3+k^2+n is prime for k = 0, 1, 2."
The following subset is also prime for k = 3: 5, 11, 17, 71, 101, 137, 227, 281, 347, 431, 641, 827, 1151, 1277, 1487. The following subset of those is also prime for k = 4: 17, 71, 101, 227, 827, 1151, 1487. The following subset of those is also prime for k = 5: 827, 1151, 1487. The "17" in A050266's n^3+n^2+17 is because k^3+k^2+17 is prime for k = 1,2,3,4,5,6,7,8,9,10. Between 10000 and 20000 there are 30 members of the k = 0,1,2 sequence, of which these 10 are also prime for k = 3: 10301, 10937, 11057, 11777, 12107, 13997, 15137, 15737, 16061, 19541. The following subset of those is also prime for k = 5: 15137, 15737, 16061. Somewhere in these sequences is a value that breaks the 11-term record of A050266 and indeed any known prime generating polynomial record. (End)

Crossrefs

Programs

  • Magma
    [p: p in PrimesUpTo(3600) | IsPrime(p+2) and IsPrime(p+12)]; // Vincenzo Librandi, Apr 09 2013
  • Mathematica
    Select[Prime[Range[600]], PrimeQ[# + 2] && PrimeQ[# + 12]&] (* Vincenzo Librandi, Apr 09 2013 *)
    Select[Prime[Range[600]],AllTrue[#+{2,12},PrimeQ]&] (* Harvey P. Dale, Jun 26 2025 *)

Formula

{n such that n prime, n+2 prime, n+12 prime} = A001359 INTERSECT A046133. - Jonathan Vos Post, May 17 2006

Extensions

Edited by R. J. Mathar and N. J. A. Sloane, Aug 13 2008

A046141 p, p+8 and p+12 are primes.

Original entry on oeis.org

5, 11, 29, 59, 71, 89, 101, 269, 389, 431, 449, 479, 491, 761, 929, 1289, 1439, 1481, 1559, 1571, 1601, 2129, 2339, 2381, 2531, 2609, 2699, 2741, 2789, 3011, 3209, 3449, 3911, 4721, 5471, 5519, 5639, 5849, 6569, 6899, 6959
Offset: 1

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Select[Range@ 7000, AllTrue[{#, # + 8, # + 12}, PrimeQ] &] (* Michael De Vlieger, Jul 24 2015, Version 10 *)
    Select[Prime[Range[1000]],AllTrue[#+{8,12},PrimeQ]&] (* Harvey P. Dale, Oct 07 2023 *)
  • PARI
    lista(nn) = forprime(p=2, nn, if (isprime(p+8) && isprime(p+12), print1(p, ", "))); \\ Michel Marcus, Jul 24 2015

A086136 Primes p such that p and p+12 are nonconsecutive primes.

Original entry on oeis.org

5, 7, 11, 17, 19, 29, 31, 41, 47, 59, 61, 67, 71, 89, 97, 101, 127, 137, 139, 151, 167, 179, 181, 227, 229, 239, 251, 257, 269, 271, 281, 337, 347, 367, 389, 397, 409, 419, 421, 431, 449, 479, 487, 491, 557, 587, 601, 607, 631, 641, 647, 727, 739, 757, 761, 809
Offset: 1

Views

Author

Labos Elemer, Jul 28 2003

Keywords

Comments

This sequence differs from A046133 because here the terms of A031930 are missing.
Complement of a=A031930 with respect to b=A046133: [b] & [not a]: this and A031930 are disjoint, but A031930 is a proper subset of A046133.

Examples

			First two deviations from A046133 are that 199=A031930(1) and 211=A031930(2) are missing. First 20 terms are equal.
		

Crossrefs

Programs

  • Mathematica
    Do[s=Prime[n]; s1=Prime[n+1]; If[PrimeQ[s+d]&& !Equal[s1-s, d], Print[s]], {n, 1, 1000}]; d=12
    ncpQ[n_]:=Module[{c=n+12},PrimeQ[c]&&NextPrime[n]!=c]; Select[Prime[ Range[ 150]],ncpQ] (* Harvey P. Dale, May 03 2012 *)

A185022 Prime p such that p, p+12, p+24 are all primes.

Original entry on oeis.org

5, 7, 17, 19, 29, 47, 59, 89, 127, 139, 167, 199, 227, 239, 257, 269, 397, 409, 419, 467, 479, 607, 619, 727, 797, 929, 997, 1009, 1039, 1277, 1279, 1427, 1447, 1459, 1487, 1499, 1559, 1597, 1697, 1709, 1777, 1877, 1889, 1987, 2087, 2129, 2269, 2399, 2609
Offset: 1

Views

Author

Salvatore Di Guida, May 19 2012

Keywords

Comments

Intersection of A046133 and A033560. - M. F. Hasler, May 19 2012

Programs

  • Mathematica
    Select[Range[50], PrimeQ[#] && PrimeQ[# + 12] && PrimeQ[# + 24] &] (* G. C. Greubel, Jun 20 2017 *)
  • PARI
    forprime(p=1,2999,isprime(p+12)&isprime(p+24)&print1(p",")) \\ M. F. Hasler, May 19 2012

A056775 Numbers k such that phi(k+12) = phi(k) + 12.

Original entry on oeis.org

5, 7, 11, 17, 19, 29, 31, 41, 45, 47, 59, 61, 65, 67, 71, 80, 89, 97, 99, 101, 112, 117, 127, 135, 137, 139, 151, 167, 171, 176, 179, 181, 196, 199, 207, 209, 211, 227, 229, 239, 251, 257, 269, 271, 272, 279, 281, 294, 304, 310, 312, 337, 347, 367, 369, 389
Offset: 1

Views

Author

Labos Elemer, Aug 17 2000

Keywords

Comments

Prime solutions are in A046133, common with primes in A015917.

Examples

			65 is a term since phi(65) = 48, phi(65+12) = phi(77) = 60 = 48 + 12.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[400],EulerPhi[#]+12==EulerPhi[#+12]&] (* Harvey P. Dale, Jan 21 2013 *)

A056776 Composite numbers k such that phi(k+12) = phi(k) + 12.

Original entry on oeis.org

45, 65, 80, 99, 112, 117, 135, 171, 176, 196, 207, 209, 272, 279, 294, 304, 310, 312, 369, 406, 429, 477, 496, 531, 592, 656, 657, 711, 752, 801, 909, 927, 944, 981, 1014, 1072, 1078, 1179, 1251, 1359, 1424, 1557, 1611, 1629, 1712, 1719, 1744, 1786, 1791
Offset: 1

Views

Author

Labos Elemer, Aug 17 2000

Keywords

Comments

There are common cases with A054902.

Examples

			656 is a term since it is composite and phi(656) = 320, phi(656+12) = phi(668) = 332 = 320 + 12.
657 is a term since it is composite and phi(657) = 432, phi(657+12) = phi(669) = 444 = 432 + 12.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[1800], CompositeQ[#] && EulerPhi[# + 12] == EulerPhi[#] + 12 &] (* Amiram Eldar, Mar 01 2020 *)
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