This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A093594 #4 Jul 12 2012 00:39:48 %S A093594 1,1,2,2,3,4,6,6,8,12,16,18,24,24,30,40,48,60,72,80,90,96,120,120,144, %T A093594 180,240,288,360,432,480,540,576,600,720,720,840,1008,1260,1440,1680, %U A093594 2016,2160,2520,2880,3024,3360,3600,3780,4032,4200,4320,5040,5040,5760 %N A093594 Farey-factorial numerators, including duplicates. %C A093594 The only repeated terms are 1!, 2!, 3!, etc. Deleting one of each leaves A092824. When written as an array with (row n)=n!*(Farey fractions of order n), The row sums are given by A093593. The n-th alternating row sum is n!/2, for n>=2. (2/n!)*(n-th row sum)=A005728(n)=number of Farey fractions of order n. %e A093594 Put the positive Farey fractions of order n into row n, %e A093594 and multiply by n!: %e A093594 1 %e A093594 1 2 %e A093594 2 3 4 6 %e A093594 6 8 12 16 18 24 ... %e A093594 Link the rows to form the sequence. %Y A093594 Cf. A005728, A092824, A093593. %K A093594 nonn,tabf %O A093594 1,3 %A A093594 _Clark Kimberling_, Apr 03 2004