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 1-4 of 4 results.

A060951 Rank of elliptic curve y^2 = x^3 - n.

Original entry on oeis.org

0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 2, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 2, 1, 0, 0, 1, 1, 1, 0, 2, 1, 1, 1, 1, 0, 2, 1, 1, 1, 1, 1, 1, 1, 2, 0, 1, 0, 1, 1, 2, 0, 0, 0, 1, 1, 0, 1, 1, 2, 0, 0, 1, 0, 1, 0, 2, 1, 1, 0, 1, 0, 2
Offset: 1

Views

Author

N. J. A. Sloane, May 10 2001

Keywords

Comments

The curves for n and -27*n are isogenous (as Noam Elkies points out--see Womack), so they have the same rank. - Jonathan Sondow, Sep 10 2013

Examples

			a(1) = A060950(27) = a(729) = 0. - _Jonathan Sondow_, Sep 10 2013
		

Crossrefs

Cf. A081120 (number of integral solutions to Mordell's equation y^2 = x^3 - n).

Programs

  • PARI
    {a(n) = if( n<1, 0, length( ellgenerators( ellinit( [ 0, 0, 0, 0, -n], 1))))} /* Michael Somos, Mar 17 2011 */
    
  • PARI
    apply( {A060951(n)=ellrank(ellinit([0,-n]))[1]}, [1..99]) \\ For version < 2.14, use ellanalyticrank(...). - M. F. Hasler, Jul 01 2024

Formula

a(n) = A060950(27*n) and A060950(n) = a(27*n), so a(n) = a(729*n). - Jonathan Sondow, Sep 10 2013

Extensions

Corrected Apr 08 2005 at the suggestion of James R. Buddenhagen. There were errors caused by the fact that Mishima lists each curve of rank two twice, once for each generator.

A002150 Numbers k for which the rank of the elliptic curve y^2 = x^3 - k is 0.

Original entry on oeis.org

1, 3, 5, 6, 8, 9, 10, 12, 14, 16, 17, 24, 27, 31, 32, 33, 34, 36, 37, 41, 42, 46, 52, 62, 64, 68, 69, 70, 73, 77, 78, 80, 82, 86, 88, 90, 92, 96, 97, 98, 99, 103, 105, 108, 111, 113, 114, 117, 119, 122, 125, 132, 133, 134, 136, 141, 142, 144, 145, 149, 154, 156, 158, 160
Offset: 1

Views

Author

Keywords

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Cf. A002152 (rank 1), A002154 (rank 2), A179136 (rank 3), A179137 (rank 4).
Cf. A060951.

Programs

  • Magma
    for k in[1..200] do if Rank(EllipticCurve([0,0,0,0,-k])) eq 0 then print k; end if; end for; // Vaclav Kotesovec, Jul 07 2019
  • PARI
    for(k=1, 200, if(ellanalyticrank(ellinit([0, 0, 0, 0, -k]))[1]==0, print1(k", "))) \\ Seiichi Manyama, Jul 06 2019
    

Extensions

Better definition from Artur Jasinski, Jun 30 2010
More terms added by Seiichi Manyama, Jul 06 2019

A179136 Parameters n for which the elliptic curve y^2=x^3-n has rank 3.

Original entry on oeis.org

174, 307, 362, 431, 503, 516, 706, 713, 741, 755, 804, 984, 1048, 1075, 1173, 1187, 1192, 1208, 1236, 1259, 1315, 1356, 1439, 1478, 1588, 1607, 1668, 1712, 1724, 1727, 1763, 1777, 1812, 1902, 1951, 1966, 1999, 2001, 2036, 2071, 2181, 2188, 2198, 2219
Offset: 1

Views

Author

Artur Jasinski, Jun 30 2010

Keywords

Crossrefs

Cf. A002150 (rank 0), A002152 (rank 1), A002154 (rank 2), A031508, A179137 (rank 4).

A179137 Parameters n for which the elliptic curve y^2=x^3-n has rank 4.

Original entry on oeis.org

2351, 3896, 4799, 4827, 5417, 5835, 6691, 6843, 9748, 9967, 10723, 11559, 12163, 12394, 12891, 13971, 14188, 14907, 15049, 15544
Offset: 1

Views

Author

Artur Jasinski, Jun 30 2010

Keywords

Crossrefs

Cf. A002150 (rank 0), A002152 (rank 1), A002154 (rank 2), A179136 (rank 3).
Cf. A031508.

Programs

  • PARI
    for(k=1, 1e4, if(ellanalyticrank(ellinit([0, 0, 0, 0, -k]))[1]==4, print1(k", "))) \\ Seiichi Manyama, Jul 07 2019

Extensions

a(11)-a(20) from Seiichi Manyama, Jul 07 2019
Showing 1-4 of 4 results.