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 A102401 #2 Feb 27 2009 03:00:00 %S A102401 0,2,14,80,512,3776,31376,290456,2970296,33276536,405440216, %T A102401 5338909736,75572075816,1144441325096,18464406889256,316212570391976, %U A102401 5729159765566376 %N A102401 a(n) is the index of the permutation of order n having the least sum of pairwise products as given by A026035. %C A102401 A026035 gives the minimum sum of products for permutations and was used to validate the results above. There is a companion index for the permutations that are the reversals of those indexed here. A formula would be very welcome. %e A102401 In the permutation table of order 7 the first instance of a row having the least sum of overlapping pairwise products can be found empirically to be: %e A102401 6 2 4 3 5 1 7 %e A102401 and this is found at index 3776. Its products are %e A102401 12 8 12 15 5 7 %e A102401 and sum is 59; a(7) of A026035 is 59. This allows us to give a(7) as 3776. %K A102401 easy,nonn %O A102401 2,2 %A A102401 Eugene McDonnell (eemcd(AT)mac.com), Feb 22 2005