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kannonboy | 9 years ago

Thanks Peff, congrats on the great release!

I came up with 19,290 using the generalized birthday formula[0] (actually after double-checking it's slightly closer to 19,291).

16,384 is the value you get using the square approximation method[1] which I believe is a bit less accurate in terms of probability, but faster to calculate. I think Git's using square approximation under the hood -- which is probably a good thing since I think it'll always yield a more conservative result.

[0]: https://en.wikipedia.org/wiki/Birthday_problem#Cast_as_a_col...

[1]: https://en.wikipedia.org/wiki/Birthday_problem#Square_approx...

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peff|9 years ago

Right, I am so used to the square approximation being used for hash collisions that I forgot it was an approximation. Thanks for setting me straight.