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Search: id:A003775
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| A003775 |
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Number of perfect matchings (or domino tilings) in P_5 X P_2n. |
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+0
3
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| 1, 8, 95, 1183, 14824, 185921, 2332097, 29253160, 366944287, 4602858719, 57737128904, 724240365697, 9084693297025, 113956161827912, 1429438110270431, 17930520634652959, 224916047725262248
(list; graph; listen)
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OFFSET
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0,2
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REFERENCES
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R. P. Stanley, Enumerative Combinatorics I, p. 292.
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LINKS
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F. Faase, Counting Hamilton cycles in product graphs
James A. Sellers, Domino Tilings and Products of Fibonacci and Pell Numbers, Journal of Integer Sequences, Vol. 5 (2002), Article 02.1.2
Index entries for sequences related to dominoes
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FORMULA
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G.f.: (1-7*x+7*x^2-x^3)/(1-15*x+32*x^2-15*x^3+x^4).
Let M be the 4 X 4 matrix |1 0 2 8 | 0 1 0 2 | 2 1 5 21| 1 1 1 8 |; then a(n) = M^n(4, 4). - DELEHAM Philippe (kolotoko(AT)wanadoo.fr), Aug 08, 2003
Lim_{n -> Inf} a(n)/a(n-1) = (3 + Sqrt(5))*(5 + Sqrt(21))/4 = 12.54375443458... - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jun 13 = 2005.
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CROSSREFS
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Row 5 of array A099390.
Sequence in context: A010565 A080208 A099298 this_sequence A121785 A116144 A074114
Adjacent sequences: A003772 A003773 A003774 this_sequence A003776 A003777 A003778
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KEYWORD
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nonn
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AUTHOR
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Frans Faase (Frans_LiXia(AT)wxs.nl)
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