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C_{n+1}*C_n*C_{n-1}^2*C_{n-2}^4*...*C_2^{2^(n-2)}, where C_k are the Catalan numbers (A000108).
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%I #12 Mar 07 2019 09:53:58

%S 1,2,10,280,235200,173859840000,98238542885683200000000,

%T 32169371027674057560745102540800000000000000000,

%U 3518552669874927170883258602839130084576857453953842493259776000000000000000000000000000000000

%N C_{n+1}*C_n*C_{n-1}^2*C_{n-2}^4*...*C_2^{2^(n-2)}, where C_k are the Catalan numbers (A000108).

%C Essentially the same as A003047, which is the main entry. [From _R. J. Mathar_, Oct 23 2008]

%D D.-Z. Du and F. K. Hwang, Combinatorial Group Testing and Its Applications, World Scientific, 2nd ed., 2000; p. 36.

%F a(n) = 2*(2n-1)*a(n-1)^2/(n+1).

%t RecurrenceTable[{a[n] == 2*(2*n-1)*a[n-1]^2/(n+1), a[1]==1}, a, {n, 1, 10}] (* _Vaclav Kotesovec_, Mar 07 2019 *)

%Y Cf. A003047, A000108.

%K nonn,easy

%O 1,2

%A _N. J. A. Sloane_, May 22 2000

%E More terms from _James A. Sellers_, May 22 2000