OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 120 terms from Colin Barker)
EXAMPLE
768 is in the sequence because there are 7 solutions to x^2 - y^2 = 768, namely (x,y) = (28,4), (32,16), (38,26), (52,44), (67,61), (98,94), (193,191).
MATHEMATICA
nn = 30000;
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