A028580 - OEIS

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A028580

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).

1, 2, 10, 280, 235200, 173859840000, 98238542885683200000000, 32169371027674057560745102540800000000000000000, 3518552669874927170883258602839130084576857453953842493259776000000000000000000000000000000000

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Essentially the same as A003047, which is the main entry. [From R. J. Mathar, Oct 23 2008]

REFERENCES

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

LINKS

Table of n, a(n) for n=1..9.

FORMULA

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

MATHEMATICA