1831956domain: NAppears in sequencesConsider sequence of fractions A066657/A066658 produced by ratios of terms in A066720; let m = smallest integer such that all fractions 1/n, 2/n, ..., (n-1)/n have appeared when we reach A066720(m) = k; sequence gives values of k; set a(n) = -1 if some fraction i/n never appears.at n=27A066848