Thanks, Milton, for indicating how you might use

(as opposed to determine) leading digits of factors:

> I just modified it [Fermat] to start with a different value

> of k based on knowing the first digits of the two factors

So _if_ you knew the first 10 digits

of the factors of RSA-576, as you claimed in

http://groups.yahoo.com/group/primenumbers/message/4760
or maybe even the first 15, as you later claimed,

what good would it do you?

Could you please tell us the number of Fermat tests

that you would then need to do, and also compare it with

the number of femtoseconds since the universe began?

David