seen = 0	\\ mask of values seen so far
unseen = 1	\\ least value not yet seen
other(p) = my (v=unseen); while (bittest(seen, v)>0 || issquarefree(p*v), v++); seen += 2^v; while (bittest(seen, unseen), unseen++); return (v)

\\ wanted = A285297
wanted = vector(2 000);
w = 1;

\\ a = A285296
a = 4;	\\ to force a(1)=1

n = 1;
while (w < #wanted, a = other(a); if (a <= #wanted, wanted[a] = n; while (w <= #wanted && wanted[w]>0, print (w " " wanted[w]); w++)); n++)
quit