OFFSET
1,1
COMMENTS
Definition: Extremal points on the Mordell elliptic curve x^3 - y^2 = d are points (x,y) such that x^3 - round(sqrt(x^3))^2 = d. For values d for successive x independent of the extensions see A077119.
For y values see A200657.
For d values see A200658.
Definition: Secondary terms occur when there exist integers k such that A200656 is divisible by k^2, A200657 is divisible by k^3 and A200658 is divisible by k^6.
Terms free of such k are primary terms; see A201047. Secondary terms are, e.g., a(6)=a(2)*2^2, a(7)=a(3)*2^2, a(17)=a(10)*2^2, a(18)=a(11)*2^2, a(19)=a(12)*2^2, a(21)=a(10)*3^2.
For successive secondary terms, see A201048.
A200216 is a subsequence of this sequence.
LINKS
Peter J. C. Moses and Artur Jasinski, Complete list of extremal points on Mordell curves x^3 - y^2 = d with quadratic extensions in range x from 1 to 10^9
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 20 2011
STATUS
approved