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%I #9 Nov 06 2015 11:21:24
%S 1,2,144,64800,101606400,411505920000,3585039575040000,
%T 59375425441812480000,1710012252724199424000000,
%U 80059353648041568632832000000,5780285333388601255290470400000000,616883611349898303167109582028800000000,93983451956379706284115479041251737600000000
%N a(n) = ((2*n)!)^2 / 2^n.
%F a(n) = A134372(n)/A000079(n).
%F a(n)*A264152(n) = A134372(n)*A006882(2*n-1)/A006882(n).
%F a(n)/A264152(n) is integer 1, 1, 24, 1620,....
%p a := n -> (2*n)!^2/2^n; seq(a(n), n=0..10);
%o (Sage)
%o a = lambda n: factorial(2*n)^2 >> n
%o [a(n) for n in range(11)]
%Y Cf. A000079, A000680, A134372, A264152.
%K nonn
%O 0,2
%A _Peter Luschny_, Nov 06 2015
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