If you want it really fast, and have 60+Gb free on your disk, you could cache the factorials up to 90k in a fixed record length file, then seek it and add/subtract to get the ranges you want.

PS: Why in the world do you need so much precision that you can't use a pretty good approximation function? Surely you're not using all of the half-million digits in the answer.

In reply to Re: how to multiply an array of number as fast as posible by SuicideJunkie
in thread how to multiply an array of number as fast as posible by baxy77bax

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