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 A139541 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. 4
 1, 3, 315, 155925, 212837625, 618718975875, 3287253918823875, 28845653137679503125, 388983632561608099640625, 7637693625347175036443671875, 209402646126143497974176151796875 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Contribution from Karol A. Penson, Oct 05 2009: (Start) Integral representation as n-th moment of a positive function on a positive halfaxis (solution of the Stieltjes moment problem), in Maple notation: a(n)=int(x^n*((1/4)*sqrt(2)*(Pi^(3/2)*2^(1/4)*hypergeom([], [1/2, 3/4], -(1/32)*x)*sqrt(x)-2*Pi*hypergeom([], [3/4, 5/4], -(1/32)*x)*GAMMA(3/4)*x^(3/4) +sqrt(Pi)*GAMMA(3/4)^2*2^(1/4)*hypergeom([], [5/4, 3/2], -(1/32)*x)*x)/(Pi^(3/2)*GAMMA(3/4)*x^(5/4))), x=0..infinity), n=0,1... . This solution may not be unique. (End) REFERENCES G. Polya and G. Szego, Problems and Theorems in Analysis II (Springer 1924, reprinted 1976), Appendix: Problem 203.1, p164. LINKS Eric Weisstein's World of Mathematics, Tournament FORMULA a(n) = A001147(n)*A001147(2*n). a(n) = A008977(n)*(A049606(n)/A001316(n))^3. - Reinhard Zumkeller, Apr 28 2008 CROSSREFS Cf. A008299, A000142, A100733, A001018. Sequence in context: A039954 A134215 A034994 * A168440 A067667 A080976 Adjacent sequences:  A139538 A139539 A139540 * A139542 A139543 A139544 KEYWORD nonn AUTHOR Reinhard Zumkeller, Apr 25 2008 STATUS approved

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Last modified January 17 18:48 EST 2019. Contains 319251 sequences. (Running on oeis4.)