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 A259687 #9 Jan 01 2021 04:32:36 %S A259687 1,1,1,81,5,7,1,1,13,1,11,1,185,1,1,7,1,27,1,1,9,1,9,9,11,3,15,325,1, %T A259687 11,17,1,1,1,1,1,5,25,33,11,7,47,801,5,193,1,1,1,19,11,13,25,21,17, %U A259687 635,5,37,1,1,1,1,177,23,1,1,43,9,1,5465,27,1,2721,1,17 %N A259687 Let m = A062695(n); a(n) is value of d in decomposition of m defined in Comments. %C A259687 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 A259687 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 A259687 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 A259687 Cf. A003273, A006991, A062695, A259680-A259687. %K A259687 nonn %O A259687 1,4 %A A259687 _N. J. A. Sloane_, Jul 04 2015 %E A259687 More terms from _Jinyuan Wang_, Jan 01 2021