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A028580
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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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2
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1, 2, 10, 280, 235200, 173859840000, 98238542885683200000000, 32169371027674057560745102540800000000000000000, 3518552669874927170883258602839130084576857453953842493259776000000000000000000000000000000000
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OFFSET
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1,2
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COMMENTS
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REFERENCES
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D.-Z. Du and F. K. Hwang, Combinatorial Group Testing and Its Applications, World Scientific, 2nd ed., 2000; p. 36.
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LINKS
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FORMULA
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a(n) = 2*(2n-1)*a(n-1)^2/(n+1).
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MATHEMATICA
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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 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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