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Search: id:A103904
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| A103904 |
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Number of perfect matchings of an n X (n+1) Aztec rectangle with the third vertex in the topmost row removed. |
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+0
3
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| 1, 2, 24, 384, 10240, 491520, 44040192, 7516192768, 2473901162496, 1583296743997440, 1981583836043018240, 4869940435459321626624, 23574053482485268906770432, 225305087149939210031640608768
(list; graph; listen)
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OFFSET
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1,2
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REFERENCES
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N. Elkies, G. Kuperberg, M. Larsen and J. Propp, Alternating sign matrices and domino tilings, Journal of Algebraic Combinatorics {\bf 1}, 111-132, 219-234 (1992).
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LINKS
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M. Ciucu, Enumeration of perfect matchings in graphs with reflective symmetry, J. Combin. Theory Ser. A 77 (1997), no. 1, 67-97
C. Krattenthaler, Schur function identities and the number of perfect matchings of Aztec holey rectangles
H. Helfgott and I. M. Gessel, Enumeration of tilings of diamonds and hexagons with defects
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FORMULA
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n(n-1)/2 * 2^(n(n-1)/2), for n>1.
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CROSSREFS
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Equals A000217(n-1) * A006125(n). Cf. A095340.
Sequence in context: A081685 A052670 A052736 this_sequence A003102 A052712 A133413
Adjacent sequences: A103901 A103902 A103903 this_sequence A103905 A103906 A103907
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KEYWORD
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nonn
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AUTHOR
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Ralf Stephan, Feb 21 2005
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