A147964 - OEIS

%I #18 Apr 12 2020 03:06:18

%S 120,691020,128047374,6519340912,156097542888,2259242749800,

%T 22815705739244,175939638868224,1099964624581680,5812510584460580,

%U 26753072198342490,109684475412107232,407515671392921520,1390695205822539984,4406577363489470616,13079027432832437440

%N Number of consistent sets of 10 irreflexive binary order relationships over n objects.

%H V. I. Rodionov, <a href="https://doi.org/10.1016/0012-365X(92)90155-9">On the number of labeled acyclic digraphs</a>, Discr. Math. 105 (1-3) (1992), 319-321.

%F a(n) = (n-4)*(n-3)*(n-2)*(n-1)*n*(n^15 - 80*n^13 - 300*n^12 + 1366*n^11 + 18300*n^10 + 117700*n^9 + 293220*n^8 - 4873571*n^7 - 63731100*n^6 - 168619940*n^5 + 2528179320*n^4 + 17989477164*n^3 - 56994404400*n^2 - 561199055760*n + 1856094609600)/3628800. - _Vaclav Kotesovec_, Apr 11 2020

%t Table[(n - 4)*(n - 3)*(n - 2)*(n - 1)*n*(n^15 - 80*n^13 - 300*n^12 + 1366*n^11 + 18300*n^10 + 117700*n^9 + 293220*n^8 - 4873571*n^7 - 63731100*n^6 - 168619940*n^5 + 2528179320*n^4 + 17989477164*n^3 - 56994404400*n^2 - 561199055760*n + 1856094609600)/3628800, {n, 5, 20}] (* _Wesley Ivan Hurt_, Apr 12 2020 *)

%Y Related sequences for the number of consistent sets of k irreflexive binary order relationships over n objects: A147796 (k = 3), A147817 (k = 4), A147821 (k = 5), A147860 (k = 6), A147872 (k = 7), A147881 (k = 8), A147883 (k = 9).

%Y Column k = 10 of A081064.

%K nonn,easy

%O 5,1

%A _R. H. Hardin_, May 04 2009

%E More terms from _Vaclav Kotesovec_, Apr 11 2020

%E Offset changed to n=5 by _Petros Hadjicostas_, Apr 11 2020