big = 1 000 000
s = 0
S = Set([])
unseen = 1
seen(v) = if (v < big, bit test(s, v), set search(S, v))
see(v) = if (v < big, s = bit or(s, 2^v), S = set union(S, Set([v]))); while (seen(unseen), unseen++)

lpf(n) = if (n==1, 1, my (f=factor(n)); f[1,1])
gpf(n) = if (n==1, 1, my (f=factor(n)); f[#f~,1])

other(n) = {
	my (z = gpf(n));
	forstep (k=ceil(unseen/z)*z, oo, z,
		if (!seen(k) && z == lpf(k),
			see(k);
			return (k);
		);
	);
}

for (n=1, 10 000, print (n " " other(n)))

quit