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 16 results. Next

A067200 Numbers m such that m^3 + 2 is prime.

Original entry on oeis.org

0, 1, 3, 5, 29, 45, 63, 65, 69, 71, 83, 105, 113, 123, 129, 143, 153, 171, 173, 189, 209, 215, 219, 231, 243, 245, 249, 263, 291, 299, 305, 311, 341, 363, 369, 395, 419, 425, 431, 435, 473, 483, 491, 495, 501, 503, 509, 515, 533, 549, 555, 561, 575, 579, 639
Offset: 1

Views

Author

Benoit Cloitre, Feb 19 2002

Keywords

Crossrefs

Cf. A144953.
Other sequences of the type "Numbers m such that m^k + k - 1 is prime": A000040 (k=1), A005574 (k=2), this sequence (k=3), A125259 (k=4), A125260 (k=5), A125261 (k=6), A125262 (k=7), A125263 (k=8), A125264 (k=10), A125265 (k=11).

Programs

Formula

a(n) = (A144953(n) - 2)^(1/3). - Zak Seidov, Sep 16 2013

A178251 Primes p such that p^3 - 2 is prime.

Original entry on oeis.org

19, 31, 37, 67, 109, 151, 211, 241, 277, 367, 439, 457, 619, 691, 727, 787, 859, 967, 1087, 1171, 1471, 1489, 1531, 1579, 1951, 2131, 2287, 2791, 2851, 2971, 3061, 3319, 3511, 3547, 3559, 3739, 4129, 4357, 4447, 4507, 4591, 4651, 4789, 4801, 4831, 4951
Offset: 1

Views

Author

Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 24 2010

Keywords

Examples

			6857 = prime(882) = 19^3 - 2, 19 = prime(8) is 1st term.
29789 = prime(3228) = 31^3 - 2, 31 = prime(11) is 2nd term.
		

Crossrefs

Programs

  • Magma
    [p: p in PrimesUpTo(5000) | IsPrime(p^3-2)]; // Vincenzo Librandi, Nov 17 2010
    
  • Mathematica
    Select[Prime[Range[10000]], PrimeQ[#^3 - 2] &] (* Vincenzo Librandi, Mar 20 2014 *)
  • PARI
    list(lim)=my(v=List()); forprime(p=2,lim, if(isprime(p^3-2), listput(v, p))); Vec(v) \\ Charles R Greathouse IV, Feb 08 2016
  • Sage
    a = list(p for p in primes(10000) if is_prime(p**3-2)) # D. S. McNeil, May 25 2010
    

Extensions

Base tag removed by D. S. McNeil, May 25 2010

A178336 Smaller member of a twin prime pair of the form (k^3 + 2, k^3 + 4).

Original entry on oeis.org

3, 29, 91127, 250049, 328511, 2146691, 47832149, 121287377, 170953877, 194104541, 693154127, 979146659, 1167575879, 1664006627, 5079577961, 6219352721, 8678316377, 10289109377, 10633486601, 13980103931, 17474794877, 28066748321, 28736971049
Offset: 1

Views

Author

Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 25 2010

Keywords

Examples

			3 = 1^3+2 = prime(2) and 5 = 1^3+4 = prime(3) are a twin prime pair, so 3 becomes the first term.
91127 = 45^3+2 = prime(8811) and 91129 = 45^3+4 = prime(8812) are a twin prime pair, so 91127 is a term.
		

References

  • Edmund Landau, Handbuch der Lehre von der Verteilung der Primzahlen, Band I, B. G. Teubner, Leipzig u. Berlin, 1909

Crossrefs

Programs

  • Mathematica
    Select[Range[3100]^3+2,PrimeQ[#]&&PrimeQ[#+2]&] (* Harvey P. Dale, May 26 2012 *)

Formula

a(n) = A178337(n)^3 + 2.

Extensions

Keyword:base removed, 2 missing terms inserted by R. J. Mathar, Jun 27 2010

A178337 Numbers k such that (k^3 + 2, n^3 + 4) is a twin prime pair.

Original entry on oeis.org

1, 3, 45, 63, 69, 129, 363, 495, 555, 579, 885, 993, 1053, 1185, 1719, 1839, 2055, 2175, 2199, 2409, 2595, 3039, 3063, 3303, 3399, 3555, 3615, 4245, 4443, 4449, 5073, 5373, 5535, 5703, 5949, 6015, 6075, 6693, 6795, 6849, 7023, 7119, 7155, 7509, 7779, 8535
Offset: 1

Views

Author

Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 25 2010

Keywords

Comments

With the exception of k = 1, all k are odd multiples of 3 with a least-significant decimal digit of 3, 5 or 9.
A178336(n) gives the values of k^3 + 2.

Examples

			1^3 + 2 = 3 = prime(2) and 3+2 = prime(3) are twin primes, so n=1 is a term.
45^3 + 2 = 91127 = prime(8811) and 91127+2 = prime(8812) are twin primes, so 45 is a term.
10893^3 + 2 = 1292535591959 = prime(48144179941) is a lower twin prime, so 10893 is a term.
		

Crossrefs

Programs

  • Magma
    [n: n in [0..9000] | IsPrime(n^3+2) and IsPrime(n^3+4)]; // Vincenzo Librandi, Nov 18 2010
  • Mathematica
    seqQ[n_] := And @@ PrimeQ[n^3 + 3 + {-1, 1}]; Select[Range[8535], seqQ] (* Amiram Eldar, Jan 11 2020*)

Extensions

Keyword:base removed by R. J. Mathar, Jun 27 2010

A188764 Primes p such that all prime factors of p-2 have exponent 3.

Original entry on oeis.org

3, 29, 127, 24391, 274627, 328511, 357913, 571789, 1157627, 1442899, 1860869, 2146691, 2924209, 5177719, 9129331, 9938377, 10503461, 12326393, 15438251, 18191449, 24642173, 26730901, 28372627, 30080233, 39651823
Offset: 1

Views

Author

Keywords

Comments

A048636 is the subsequence of terms where there is only one prime divisor of p-2. - M. F. Hasler, Jan 13 2025

Examples

			30080233-2 = 311^3, 39651823-2 = 11^3*31^3, ...
3-2 = 1 has no prime factors, so is trivially a member.
		

Crossrefs

Subsequence of A144953; A048636 is a subsequence.

Programs

  • Mathematica
    Prepend[Select[Table[Prime[n],{n,3000000}],Length[Union[Last/@FactorInteger[#-2]]]==1&&Union[Last/@FactorInteger[#-2]]=={3}&], 3]
    Prepend[Select[Prime[Range[25*10^5]],Union[FactorInteger[#-2][[All,2]]]=={3}&], 3] (* Harvey P. Dale, Nov 22 2018 *)
    seq[lim_] := Select[Select[Range[Floor[Surd[lim-2, 3]]], SquareFreeQ]^3 + 2, PrimeQ]; seq[4*10^7] (* Amiram Eldar, Jan 18 2025 *)
  • PARI
    list(lim)=my(v=List()); forsquarefree(k=1,sqrtnint(lim\1-2,3), my(p=k[1]^3+2); if(isprime(p), listput(v,p))); Vec(v) \\ Charles R Greathouse IV, Jan 14 2025

Formula

a(n) >> n^3. - Charles R Greathouse IV, Jan 14 2025

Extensions

a(1) = 3 inserted by Charles R Greathouse IV, Jan 14 2025

A216977 Primes of the form n^5+2.

Original entry on oeis.org

2, 3, 59051, 161053, 759377, 14348909, 90224201, 345025253, 601692059, 12762815627, 73439775751, 183765996901, 296709280759, 503756397101, 576650390627, 657748550153, 1572763671877, 1751989905403, 1880287678127, 2389769101501, 3101364196877, 3201078401359
Offset: 1

Views

Author

Michel Lagneau, Sep 21 2012

Keywords

Comments

Subsequence of A053788. [Bruno Berselli, Sep 21 2012]

Crossrefs

Programs

  • Magma
    [a: n in [0..400] | IsPrime(a) where a is n^5+2]; // Vincenzo Librandi, Mar 15 2013
  • Mathematica
    lst={}; Do[p=n^5+2; If[PrimeQ[p], AppendTo[lst, p]], {n, 6!}]; lst
    Select[Table[n^5 + 2, {n, 0, 400}], PrimeQ] (* Vincenzo Librandi, Mar 15 2013 *)
  • PARI
    v=select(n->isprime(n^5+2),vector(2000,n,n-1)); /* A216976 */
    vector(#v, n, v[n]^5+2)
    /* Joerg Arndt, Sep 21 2012 */
    

A216979 Primes of the form n^6+2.

Original entry on oeis.org

2, 3, 3518743763, 17596287803, 282429536483, 54980371265627, 93385106978411, 110322650964683, 151939915084883, 1363532208525371, 1870004703089603, 3684302682180851, 5257948522194371, 15813440003753003, 22416464978706683, 33227552537453171, 80425212553252451
Offset: 1

Views

Author

Michel Lagneau, Sep 21 2012

Keywords

Crossrefs

Programs

  • Magma
    [a: n in [0..700] | IsPrime(a) where a is n^6 + 2 ]; // Vincenzo Librandi, Oct 12 2012
  • Mathematica
    lst={}; Do[p=n^6+2; If[PrimeQ[p], AppendTo[lst, p]], {n, 6!}]; lst
    Select[Table[n^6 + 2, {n, 0, 700}], PrimeQ] (* Vincenzo Librandi, Oct 12 2012 *)
  • PARI
    v=select(n->isprime(n^6+2),vector(2000,n,n-1)); /* A216978 */
    vector(#v, n, v[n]^6+2)
    /* Joerg Arndt, Sep 21 2012 */
    

A164520 Primes p such that p-2 is the product of exactly 2 distinct cubes of primes.

Original entry on oeis.org

274627, 328511, 1860869, 2146691, 2924209, 9129331, 9938377, 10503461, 15438251, 24642173, 26730901, 28372627, 39651823, 61629877, 105823819, 125751503, 136590877, 151419439, 194104541, 426957779, 573856193
Offset: 1

Views

Author

Keywords

Examples

			274627 - 2 = 5^3*13^3, 328511 - 2 = 3^3*23^3,..
		

Crossrefs

Programs

  • Mathematica
    f3[n_]:=FactorInteger[n][[1,2]]==3&&Length[FactorInteger[n]]==2&&FactorInteger[n][[2,2]]==3; lst={};Do[p=Prime[n];If[f3[p-2],AppendTo[lst,p]],{n,4,4*9!}];lst
  • PARI
    forprime(p=3,1e9,if(ispower(p-2,3,&n)&&!issquare(n)&&bigomega(n)==2,print1(p",")))

Extensions

Program by Charles R Greathouse IV, Oct 12 2009

A176722 Primes of the form k^3 + 13, k >= 0.

Original entry on oeis.org

13, 229, 1013, 1741, 39317, 64013, 74101, 157477, 438989, 551381, 830597, 1906637, 2000389, 4096013, 7077901, 9261013, 10941061, 15625013, 16003021, 21024589, 24897101, 27000013, 69934541, 74088013, 79507013, 93576677, 122023949
Offset: 1

Views

Author

Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Apr 25 2010

Keywords

Comments

Necessarily, k = 6 * j or k = 6 * j + 4.
Values of k corresponding to terms of the sequence: 0, 6, 10, 12, 34, 40, 42, 54, 76, 82, 94, 124, 126, 160, 192, 210, 222, 250, 252, 276, 292, 300, 412, 420, 430, 454, 496, 502, 570, 586, 612, 622, 640, 670, 684, 712, 720, 724, 726, 756, 784, 822, 826, 874, 882, 894, 934, 952, 964, 1006, 1056.

Examples

			0^3 + 13 = 13 = prime(6) = a(1);
6^3 + 13 = 229 = prime(50) = a(2);
300^3 + 13 = 27000013 = prime(1683067) = a(22).
		

References

  • H. Rademacher, Topics in Analytic Number Theory, Springer-Verlag Berlin, 1973.

Crossrefs

Programs

  • Magma
    [a: n in [0..500]|IsPrime(a) where a is n^3+13] // Vincenzo Librandi, Dec 22 2010
  • Maple
    select(isprime,[seq(seq((6*j+m)^3+13,m=[0,4]),j=0..1000)]); # Robert Israel, Jun 28 2018
  • Mathematica
    Select[Range[0,1000]^3+13,PrimeQ]  (* Harvey P. Dale, Mar 12 2011 *)

A178506 Lesser of a "near cube" twin prime pair (k^3 - 4, k^3 - 2).

Original entry on oeis.org

3371, 8120597, 69426527, 108531329, 176558477, 1207949621, 2379270371, 3477265871, 3560550179, 4227952109, 8012005997, 12665630687, 13060888871, 15832158827, 15945922409, 18337088849, 20279414579, 22354272509, 30283802609, 60559558979, 70496180087, 98035951127
Offset: 1

Views

Author

Ulrich Krug (leuchtfeuer37(AT)gmx.de), May 29 2010

Keywords

Comments

p + 2 = k^3 - 2 is form of "near(est) cube" prime smaller than cube number k^3, as k^3 - 1 = (k-1) * (k^2 + k + 1), only prime for k=2.

Examples

			p = 3371 = prime(475) = 15^3 - 4, (p, p+2) is twin prime pair tp(90), 3371 is the first term.
		

Crossrefs

Programs

  • Mathematica
    Select[Range[10^4]^3 - 4, And @@ PrimeQ[# + {0, 2}] &] (* Amiram Eldar, Dec 25 2019 *)

Extensions

a(13) corrected and more terms from Amiram Eldar, Dec 25 2019
Showing 1-10 of 16 results. Next