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A147964 Number of consistent sets of 10 irreflexive binary order relationships over n objects. 8
120, 691020, 128047374, 6519340912, 156097542888, 2259242749800, 22815705739244, 175939638868224, 1099964624581680, 5812510584460580, 26753072198342490, 109684475412107232, 407515671392921520, 1390695205822539984, 4406577363489470616, 13079027432832437440 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,1

LINKS

Table of n, a(n) for n=5..20.

V. I. Rodionov, On the number of labeled acyclic digraphs, Discr. Math. 105 (1-3) (1992), 319-321.

FORMULA

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

MATHEMATICA

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 *)

CROSSREFS

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).

Column k = 10 of A081064.

Sequence in context: A127232 A208191 A166351 * A172857 A308327 A172897

Adjacent sequences:  A147961 A147962 A147963 * A147965 A147966 A147967

KEYWORD

nonn,easy

AUTHOR

R. H. Hardin, May 04 2009

EXTENSIONS

More terms from Vaclav Kotesovec, Apr 11 2020

Offset changed to n=5 by Petros Hadjicostas, Apr 11 2020

STATUS

approved

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Last modified August 12 20:18 EDT 2022. Contains 356077 sequences. (Running on oeis4.)