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A008977 (4n)!/(n!)^4. 14
1, 24, 2520, 369600, 63063000, 11732745024, 2308743493056, 472518347558400, 99561092450391000, 21452752266265320000, 4705360871073570227520, 1047071828879079131681280, 235809301462142612780721600 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Number of paths of length 4n in an n X n X n X n grid from (0,0,0,0) to (n,n,n,n).

LINKS

T. D. Noe, Table of n, a(n) for n=0..100

R. M. Dickau, Paths through a 4-D lattice

FORMULA

a(n) = A139541(n)*(A001316(n)/A049606(n))^3. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Apr 28 2008

Self-convolution of A178529, where A178529(n) = (4^n/n!^2) * Product_{k=0..n-1} (8*k+1)*(8*k+3).

G.f.: hypergeom([1/8, 3/8], [1], 256*x)^2 - Mark van Hoeij, Nov 16 2011

EXAMPLE

a(13)=52!/(13!)^4=53644737765488792839237440000 is the number of ways of dealing the four hands in Bridge or Whist - Henry Bottomley (se16(AT)btinternet.com), Oct 06 2000

MAPLE

A008977 := n->(4*n)!/(n!)^4;

MATHEMATICA

Table[(4n)!/(n!)^4, {n, 0, 16}] (* From Harvey P. Dale, Oct 24 2011 *)

CROSSREFS

Cf. A000984, A006480, A008978, A178529.

Sequence in context: A107675 A173115 A202927 * A159392 A064596 A092706

Adjacent sequences:  A008974 A008975 A008976 * A008978 A008979 A008980

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 16 02:30 EST 2012. Contains 205860 sequences.