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Search: id:A139541
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| A139541 |
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There are 4*n players who wish to play bridge at n tables. Each player must have another player as partner and each pair of partners must have another pair as opponents. The choice of partners and opponents can be made in exactly a(n)=(4*n)!/(n!*8^n) different ways. |
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+0
2
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| 1, 3, 315, 155925, 212837625, 618718975875, 3287253918823875, 28845653137679503125, 388983632561608099640625, 7637693625347175036443671875, 209402646126143497974176151796875
(list; graph; listen)
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OFFSET
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0,2
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REFERENCES
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G. Polya and G. Szego, Problems and Theorems in Analysis II (Springer 1924, reprinted 1976), Appendix: Problem 203.1, p164.
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LINKS
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Eric Weisstein's World of Mathematics, Tournament
Index entries for sequences related to tornaments.
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FORMULA
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a(n) = A001147(n)*A001147(2*n).
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CROSSREFS
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Cf. A008299, A000142, A100733, A001018.
Adjacent sequences: A139538 A139539 A139540 this_sequence A139542 A139543 A139544
Sequence in context: A039954 A134215 A034994 this_sequence A067667 A080976 A112895
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KEYWORD
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nonn,new
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AUTHOR
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Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Apr 25 2008
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