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.
%I A054504 #32 Feb 16 2025 08:32:42 %S A054504 6,7,11,13,14,20,21,23,29,32,34,39,42,45,46,47,51,53,58,59,60,61,62, %T A054504 66,67,69,70,74,75,77,78,83,84,85,86,87,88,90,93,95,96,102,103,104, %U A054504 109,110,111,114,115,116,118,123,124,130,133,135,137,139,140,146,147,149,153,155 %N A054504 Numbers n such that Mordell's equation y^2 = x^3 + n has no integral solutions. %C A054504 Mordell's equation has a finite number of integral solutions for all nonzero n. Gebel computes the solutions for n < 10^5. Sequence A081121 gives n for which there are no integral solutions to y^2 = x^3 - n. See A081119 for the number of integral solutions to y^2 = x^3 + n. - _T. D. Noe_, Mar 06 2003 %C A054504 Numbers n such that A081119(n) = 0. - _Charles R Greathouse IV_, Apr 29 2015 %D A054504 T. M. Apostol, Introduction to Analytic Number Theory, Springer-Verlag, page 192. %D A054504 J. Gebel, A. Petho and H. G. Zimmer, On Mordell's equation, Compositio Mathematica 110 (3) (1998), 335-367. %H A054504 T. D. Noe, <a href="/A054504/b054504.txt">Table of n, a(n) for n = 1..6603</a> (from Gebel) %H A054504 Pantelis Andreou, Stavros Konstantinidis, and Taylor J. Smith, <a href="https://arxiv.org/abs/2403.08707">Improved Randomized Approximation of Hard Universality and Emptiness Problems</a>, arXiv:2403.08707 [cs.DS], 2024. See p. 16. %H A054504 Ryan D'Mello, <a href="http://arxiv.org/abs/1410.0078">Marshall Hall's Conjecture and Gaps Between Integer Points on Mordell Elliptic Curves</a>, arXiv preprint arXiv:1410.0078, 2014 %H A054504 J. Gebel, <a href="/A001014/a001014.txt">Integer points on Mordell curves</a> [Cached copy, after the original web site tnt.math.se.tmu.ac.jp was shut down in 2017] %H A054504 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MordellCurve.html">Mordell Curve</a> %t A054504 m = 155; f[_List] := ( xm = 2 xm; ym = Ceiling[xm^(3/2)]; %t A054504 Complement[Range[m], Outer[Plus, Range[0, ym]^2, -Range[-xm, xm]^3] //Flatten //Union]); xm=10; FixedPoint[f, {}] (* _Jean-François Alcover_, Apr 28 2011 *) %Y A054504 Cf. A081119, A081121. %K A054504 nonn,nice %O A054504 1,1 %A A054504 _N. J. A. Sloane_, Apr 08 2000 %E A054504 Apostol gives all values of n < 100. Extended by _David W. Wilson_, Sep 25 2000