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A002638 a(n) = (number of nonisomorphic nontransitive prime tournaments on n nodes) - Moebius(n).
(Formerly M0913 N0345)
2

%I M0913 N0345 #36 Oct 04 2020 11:05:32

%S -1,1,2,3,12,52,456,6873,191532,9733032,903753248,154108311046,

%T 48542114686912,28401423719121392,31021002160355166800,

%U 63530415842308265086523,244912778438520759443245824,1783398846284777975419599903948,24605641171260376770598003978281472

%N a(n) = (number of nonisomorphic nontransitive prime tournaments on n nodes) - Moebius(n).

%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Pontus von Brömssen, <a href="/A002638/b002638.txt">Table of n, a(n) for n = 1..76</a>

%H J. W. Moon and M. Goldberg, <a href="http://projecteuclid.org/euclid.dmj/1077378978">On the composition of two tournaments</a>, Duke Mathematical Journal, vol.37, no.2 (1970), pp.323-332. (subscription required)

%H J. W. Moon and M. Goldberg, <a href="/A000568/a000568_2.pdf">On the composition of two tournaments</a>, Duke Mathematical Journal 37.2 (1970): 323-332. [Annotated scans of pages 331 and 332 only]

%H <a href="/index/To#tournament">Index entries for sequences related to tournaments</a>

%F a(1)=-1, a(n) = A000568(n) - Sum_{d|n, d!=1, d!=n} (a(d) * A000568(n / d). - _Sean A. Irvine_, Oct 19 2015

%F a(n) = A259106(n) - A008683(n). - _Pontus von Brömssen_, Oct 03 2020

%Y Cf. A000568, A008683, A259106.

%K sign

%O 1,3

%A _N. J. A. Sloane_

%E Definition clarified by _N. J. A. Sloane_, Jun 23 2015

%E More terms from _Sean A. Irvine_, Oct 19 2015

%E a(19) from _Pontus von Brömssen_, Oct 03 2020

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Last modified April 23 13:04 EDT 2024. Contains 371913 sequences. (Running on oeis4.)