A066849 Consider 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 m; set a(n) = -1 if some fraction i/n never appears.
1, 2, 3, 401, 113, 22, 75, 401, 1986, 6547, 1110, 5949, 7952, 2445, 5578, 172617, 2590, 1986, 17471, 41341, 13631, 20900, 14063, 121563, 86009, 17648, 392866, 140171, 59293, 257162, 68370, 172617, 226693, 89942, 489653, 151601, 153287, 231508, 860521, 999664, 479352, 751180, 475540, 1312350, 246470, 287004, 84285, 1137690, 363942, 86009, 276267, 603972, 219888, 1139722, 1525515, 5227193, 1486480, 206546, 379708, 1244626, 374003, 590152, 7230480, 1903679, 1834403
Offset: 1
Examples
3/4 does not occur until we reach A066720(401) = 2436 and then we see A066720(320)/A066720(401) = 1827/2436 = 3/4. Therefore a(4) = 401.
Extensions
Corrected by John W. Layman, Feb 05 2002
Greatly extended by David Applegate, Feb 13 2002