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 A259685 #9 Jan 01 2021 04:28:01 %S A259685 2,4,2,56,1,2,1,1,6,1,4,4,104,2,4,1,12,4,1,8,2,6,1,2,5,1,2,204,1,2,4, %T A259685 1,4,3,2,1,1,12,20,3,20,4,40,3,132,6,3,2,6,2,82,17,11,4,333,14,12,6,5, %U A259685 2,1,52,1,12,2,29,1,1,1972,7,24,1504,20,360,10,2952 %N A259685 Let m = A062695(n); a(n) is value of b in decomposition of m defined in Comments. %C A259685 Let m = A062695(n). Write m*y^2 = x^3 - x as m*square = A*B*(A-B)*(A+B) where A and B are the numerator and denominator of x. Then A, B, A-B, A+B have the form s*a^2, t*b^2, u*c^2, v*d^2 for some decomposition of m as s*t*u*v and some natural numbers a,b,c,d. These eight numbers are given in A259680-A259687. %H A259685 G. Kramarz, <a href="http://dx.doi.org/10.1007/BF01451411">All congruent numbers less than 2000</a>, Math. Annalen, 273 (1986), 337-340. %H A259685 G. Kramarz, <a href="/A003273/a003273.pdf">All congruent numbers less than 2000</a>, Math. Annalen, 273 (1986), 337-340. [Annotated, corrected, scanned copy] %Y A259685 Cf. A003273, A006991, A062695, A259680-A259687. %K A259685 nonn %O A259685 1,1 %A A259685 _N. J. A. Sloane_, Jul 04 2015 %E A259685 More terms from _Jinyuan Wang_, Jan 01 2021