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A259684
Let m = A062695(n); a(n) is value of a in decomposition of m defined in Comments.
0
3, 5, 3, 5, 2, 1, 3, 4, 1, 1, 1, 9, 153, 7, 7, 6, 13, 5, 1, 17, 1, 11, 4, 1, 4, 4, 11, 253, 4, 1, 1, 1, 1, 5, 5, 2, 8, 1, 1, 4, 103, 39, 29, 2, 5, 19, 8, 7, 1, 1, 163, 4, 8, 63, 44, 23, 35, 7, 2, 5, 4, 5, 13, 17, 1, 12, 5, 8, 193, 22, 25, 65, 29, 481, 1, 85, 1
OFFSET
1,1
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
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jul 04 2015
EXTENSIONS
More terms from Jinyuan Wang, Jan 01 2021
STATUS
approved