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Search: id:A099116
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| A099116 |
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Number of rhombus tilings of a hexagon with side lengths 2n+2,2n,2n+2,2n+2,2n,2n+2 which contain the rhombus above and next to the center of the hexagon. |
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1
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| 812, 579667803, 235948437342837440, 52366358060537007928863206000, 6262970727027052056580468670430288168750000, 401820562589647140572840734882930708995214500792163500000000
(list; graph; listen)
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OFFSET
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1,1
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LINKS
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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
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PROGRAM
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(PARI) a(n)=(1/3+4*binomial(2*n, n)^3/binomial(6*n+4, 3*n+2))*prod(i=1, 2*n+2, prod(j=1, 2*n, prod(k=1, 2*n+2, (i+j+k-1)/(i+j+k-2))))
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CROSSREFS
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Cf. A099112-A099117, A008793.
Sequence in context: A045228 A158667 A035854 this_sequence A015159 A064583 A105989
Adjacent sequences: A099113 A099114 A099115 this_sequence A099117 A099118 A099119
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KEYWORD
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nonn
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AUTHOR
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Ralf Stephan, Oct 01 2004
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