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A099113 Number of rhombus tilings of a hexagon with all sides of length 2n+1 which contain the rhombus above and next to the center of the hexagon. 0
364, 94682016, 13704096621766720, 1074416738842280125146121600, 45276656003305722314718295417920118125000, 1022271041965503132822786100650613600920143229195000000000 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

M. Fulmek and C. Krattenthaler, [math/9909038] The number of rhombus tilings of a symmetric hexagon which contain a fixed rhombus on the symmetry axis, II

PROG

(PARI) a(n)=(1/3+1/3*binomial(2*n, n)^3/binomial(6*n+2, 3*n+1))*prod(i=1, 2*n+1, prod(j=1, 2*n+1, prod(k=1, 2*n+1, (i+j+k-1)/(i+j+k-2))))

CROSSREFS

Cf. A099112-A099117, A008793.

Sequence in context: A140935 A022196 A098252 * A073304 A011763 A116354

Adjacent sequences:  A099110 A099111 A099112 * A099114 A099115 A099116

KEYWORD

nonn

AUTHOR

Ralf Stephan, Oct 01 2004

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Last modified February 15 14:37 EST 2012. Contains 205822 sequences.