Euler 173

{

t = 1000000;    \\ tiles

xlow = floor(sqrt(t));
xhigh = floor(t/4)+1;

s = floor((xlow-1)/2);
s *= (s+1); \\ running total

x2 = xlow*xlow;

for(x=xlow+1,xhigh,

    x2 += x+x-1;

    s += floor((x - ceil(sqrt(x2-t)))/2);

);

print(s);

}