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.

A062695 Squarefree n such that the elliptic curve n*y^2 = x^3 - x arising in the "congruent number" problem has rank 2.

Original entry on oeis.org

34, 41, 65, 137, 138, 145, 154, 161, 194, 210, 219, 226, 257, 265, 291, 299, 313, 323, 330, 353, 371, 386, 395, 410, 426, 434, 442, 457, 465, 505, 514, 546, 561, 602, 609, 651, 658, 674, 689, 721, 723, 731, 761, 777, 793, 866, 889, 890, 905, 915, 985, 987, 995
Offset: 1

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Author

Noam D. Elkies, Jul 04 2001

Keywords

Comments

These n are precisely the primitive congruent numbers (A006991) with n==1, n==2, or n==3 (mod 8). - T. D. Noe, Aug 02 2006

Crossrefs

Programs

  • PARI
    r(n)=ellanalyticrank(ellinit([0,0,0,-n^2,0]))[1]
    for(n=1,1e3,if(issquarefree(n)&&r(n)==2,print1(n", "))) \\ Charles R Greathouse IV, Sep 01 2011; corrected by Frank M Jackson, Aug 04 2016

Extensions

More terms from Jinyuan Wang, Dec 12 2020

A194687 Least k such that the rank of the elliptic curve y^2 = x^3 - k^2*x is n, or -1 if no such k exists.

Original entry on oeis.org

1, 5, 34, 1254, 29274, 48272239, 6611719866
Offset: 0

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Author

Keywords

Comments

Fermat found a(0), Biling found a(1), and Wiman found a(2)-a(4). Rogers found upper bounds on a(5) and a(6) equal to their true value; Rathbun and an unknown author verified them as a(5) and a(6), respectively.
a(7) <= 797507543735, see Rogers 2004.

References

  • G. Billing, "Beiträge zur arithmetischen theorie der ebenen kubischen kurven geschlechteeins", Nova Acta Reg. Soc. Sc. Upsaliensis (4) 11 (1938), Nr. 1. Diss. 165 S.
  • N. Rogers, "Elliptic curves x^3 + y^2 = k with high rank", PhD Thesis in Mathematics, Harvard University (2004).
  • A. Wiman, "Über rationale Punkte auf Kurven y^2 = x(x^2-c^2)", Acta Math. 77 (1945), pp. 281-320.

Crossrefs

Programs

  • PARI
    r(n)=ellanalyticrank(ellinit([0,0,0,-n^2,0]))[1]
    rec=0;for(n=1,1e4,t=r(n);if(t>rec,rec=t;print("r("n") = "t)))

Extensions

Escape clause added to definition by N. J. A. Sloane, Jul 01 2024

A319510 Rank of elliptic curve y^2 = x^3 - n^2 * x.

Original entry on oeis.org

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

Views

Author

Seiichi Manyama, Sep 24 2018

Keywords

Crossrefs

Programs

  • PARI
    {a(n) = ellanalyticrank(ellinit([0, 0, 0, -n^2, 0]))[1]}

Formula

a(n) = A060952(n^2).
a(A003273(n)) > 0.
a(A194687(n)) = n.
Empirical: a(n) = a(4*n). - Jose Aranda, Jul 02 2024

A062694 Squarefree n such that the elliptic curve n*y^2 = x^3 - x arising in the "congruent number" problem has rank 3 and nontrivial SHA[2].

Original entry on oeis.org

42486, 68839, 80189, 82205, 83845, 88502, 92045, 112326, 116645, 125749, 142222, 182005, 199805, 202742, 270805, 275286, 282613, 287246, 295222, 342205, 372742, 392502, 440453, 450079, 473263, 477581, 487302, 488047
Offset: 0

Views

Author

Noam D. Elkies, Jul 04 2001

Keywords

Comments

Conjectural, as detailed in the pages from which it is extracted (see the first few links at the web site mentioned for details), but the conjecture is supported by much numerical and theoretical evidence.

Crossrefs

Showing 1-4 of 4 results.