A259682 Let m = A062695(n); a(n) is value of u in decomposition of m defined in Comments.

1, 1, 5, 1, 23, 1, 7, 1, 1, 3, 1, 1, 257, 5, 1, 23, 1, 1, 1, 1, 1, 1, 79, 1, 71, 1, 17, 457, 1, 1, 1, 1, 1, 7, 21, 1, 1, 1, 1, 103, 1, 17, 1, 1, 1, 1, 1, 1, 1, 1, 5, 47, 199, 1, 7, 37, 1081, 13, 3, 17, 3, 1, 3, 1, 7, 167, 19, 1, 1, 239, 1, 1, 1, 1, 1, 1, 1, 103

Offset: 1

Author

N. J. A. Sloane, Jul 04 2015

Keywords

• nonn

Comments

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.

Links

• G. Kramarz, All congruent numbers less than 2000, Math. Annalen, 273 (1986), 337-340.
• G. Kramarz, All congruent numbers less than 2000, Math. Annalen, 273 (1986), 337-340. [Annotated, corrected, scanned copy]

Crossrefs

Cf. A003273, A006991, A062695, A259680-A259687.

Extensions

More terms from Jinyuan Wang, Jan 01 2021