A259686 Let m = A062695(n); a(n) is value of c in decomposition of m defined in Comments.

1, 3, 1, 17, 1, 3, 1, 3, 5, 1, 5, 7, 7, 3, 1, 1, 5, 11, 1, 15, 5, 7, 1, 1, 1, 1, 1, 7, 1, 9, 15, 1, 1, 1, 1, 5, 9, 7, 17, 1, 97, 7, 799, 11, 49, 17, 1, 3, 1, 1, 63, 1, 1, 55, 161, 3, 1, 1, 1, 1, 1, 161, 7, 1, 1, 1, 1, 7, 3783, 1, 7, 1697, 21, 319, 21, 911, 3, 1

Offset

1,2

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

Table of n, a(n) for n=1..78.

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.

Sequence in context: A096611 A176666 A259031 * A350079 A162313 A188645

Adjacent sequences: A259683 A259684 A259685 * A259687 A259688 A259689

Keyword

nonn

Author

N. J. A. Sloane, Jul 04 2015

Extensions

More terms from Jinyuan Wang, Jan 01 2021

Status

approved