allocate mem(2^30)

tr(v)=if (v>=0, 1+2*v, -2*v)
big = 100000
s = []
S = []
seen(z)=my (x=tr(real(z)),y=tr(imag(z)));if (max(x,y)>big, setsearch(S,z), x>#s, 0, bittest(s[x],y))
see(z)=my (x=tr(real(z)),y=tr(imag(z)));if (max(x,y)>big, S=setunion(S,Set(z)); return, x>#s, s=concat(s,vector(x-#s))); s[x]=bitor(s[x],2^y)

{
	for (n = 1, #a = vector(10 000),
		for (k = 1, n-2,
			slope = (a[n-1]-a[k])/(n-1-k);
			\\ slope encoded as a complex number
			z = numerator(slope) + I*denominator(slope);
			if (!seen(z),
				\\ new slope
				see(z);
				a[n]++;
			);
		);

		print (n " " a[n]);
	);
}

quit