11 lines
266 B
Lua
11 lines
266 B
Lua
function Binomial( n, k )
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if k > n then return nil end
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if k > n/2 then k = n - k end -- (n k) = (n n-k)
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numer, denom = 1, 1
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for i = 1, k do
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numer = numer * ( n - i + 1 )
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denom = denom * i
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end
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return numer / denom
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end
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