OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 1600 terms from Colin Barker)
EXAMPLE
480 is in the sequence because there are 8 solutions to x^2 - y^2 = 480, namely (x,y) = (22,2), (23,7), (26,14), (29,19), (34,26), (43,37), (62,58), (121,119).
MATHEMATICA
nn = 3000;
t = Table[0, {nn}];
Do[n = x^2 - y^2; If[n <= nn, t[[n]]++], {x, nn}, {y, 0, x - 1}];
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Colin Barker, Apr 22 2015
STATUS
approved