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A049288 Number of nonisomorphic circulant tournaments, i.e., Cayley tournaments for cyclic group of order 2n-1. 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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Further values for prime-squared orders can be found in A038789.

There is an easy formula for prime orders. Formulae are also known for squarefree and prime-squared orders.

LINKS

Table of n, a(n) for n=1..37.

B. Alspach, On point-symmetric tournaments, Canad. Math. Bull., 13 (1970), 317-323. [Annotated copy] See r(n).

B. Alspach, On point-symmetric tournaments, Canad. Math. Bull., 13 (1970), 317-323. 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 prime-power 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 2n-1. - 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

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Last modified February 22 06:17 EST 2018. Contains 299430 sequences. (Running on oeis4.)