

A049288


Number of nonisomorphic circulant tournaments, i.e., Cayley tournaments for cyclic group of order 2n1.


7



1, 1, 1, 2, 3, 4, 6, 16, 16, 30, 88, 94, 205, 457, 586, 1096, 3280, 5472, 7286, 21856, 26216, 49940, 174848, 182362, 399472, 1048576, 1290556, 3355456, 7456600, 9256396, 17895736, 59654816, 89478656, 130150588, 390451576, 490853416, 954437292
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OFFSET

1,4


COMMENTS

Further values for primesquared orders can be found in A038789.
There is an easy formula for prime orders. Formulae are also known for squarefree and primesquared orders.


LINKS

Table of n, a(n) for n=1..37.
B. Alspach, On pointsymmetric tournaments, Canad. Math. Bull., 13 (1970), 317323. [Annotated copy] See r(n).
B. Alspach, On pointsymmetric tournaments, Canad. Math. Bull., 13 (1970), 317323. See r(n).
V. A. Liskovets, Some identities for enumerators of circulant graphs, arXiv:math/0104131 [math.CO], 2001.
V. A. Liskovets and R. Poeschel, On the enumeration of circulant graphs of primepower and squarefree orders
R. Poeschel, Publications
Index entries for sequences related to tournaments


FORMULA

a(n) <= A002086(n).  Andrew Howroyd, Apr 28 2017
a(n) = A002086(n) for squarefree 2n1.  Andrew Howroyd, Apr 28 2017


CROSSREFS

Cf. A002086, A002087, A038789, A049297, A049287, A049289, A060966.
Sequence in context: A204540 A280592 A002087 * A102946 A026094 A285191
Adjacent sequences: A049285 A049286 A049287 * A049289 A049290 A049291


KEYWORD

nonn,nice


AUTHOR

Valery A. Liskovets


EXTENSIONS

a(14)a(37) from Andrew Howroyd, Apr 28 2017
Reference to Alspach (1970) corrected by Andrew Howroyd, Apr 28 2017


STATUS

approved



