Problem 307

Chip Defects

`k` defects are randomly distributed amongst `n`
integrated-circuit chips produced by a factory (any number of defects
may be found on a chip and each defect is independent of the other
defects).

Let p(`k,n`) represent the probability that there is a chip with at least 3 defects.

For instance p(3,7) 0.0204081633.

Find p(20 000, 1 000 000) and give your answer rounded to 10 decimal places in the form 0.abcdefghij

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These problems are part of
Project Euler
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CC BY-NC-SA 2.0 UK
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