%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