

A277257


Multitable menage seating arrangements: T(n,k) for n,k >= 1 equals the number of ways to seat n*k married couples at n round tables with 2*k seats each, such that (i) the gender of persons alternates around each table; and (ii) spouses do not sit next to each other.


2



0, 8, 0, 96, 384, 12, 3456, 460800, 236160, 96, 168960, 3065610240, 125962905600, 764467200, 3120, 12211200, 51115799347200, 453840358706380800, 226918953109094400, 6383697868800, 115200, 1196052480, 1816224465420288000, 6896429934345052028928000
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OFFSET

1,2


COMMENTS

Tables and seats are labeled. For unlabeled version, see A277265.


LINKS

Table of n, a(n) for n=1..24.


FORMULA

T(n,k) = A277256(n,k) * 2^n * (n*k)!.


EXAMPLE

Table T(n,k):
n=1: 0, 0, 12, 96, 3120, 115200, ...
n=2: 8, 384, 236160, 764467200, ...
n=3: 96, 460800, 125962905600, ...
n=4: 3456, 3065610240, 453840358706380800, ...
...


CROSSREFS

Cf. A059375 (row n=1), A277265.
Sequence in context: A079137 A181689 A221887 * A121770 A221379 A013376
Adjacent sequences: A277254 A277255 A277256 * A277258 A277259 A277260


KEYWORD

nonn,tabl


AUTHOR

Max Alekseyev, Oct 07 2016


STATUS

approved



