Strong PRNGs

[Carl Ellison]

Someone wrote:

>	for each bit in the 512-bit register, if the bit is a 1, add the
>	corresponding array entry into a 521-bit accumulator (init'd to 0
>	at the start of this pass), modulo a 521-bit prime.
>                                            ^^^
>                                           is this correct?
>

Yup.  512 + 8 + 1 = 521

512:	for the seed for next time
8:	for the output byte
1:	slop, since numbers mod a 521 bit prime won't give a uniform
	distribution of the top bit

 - Carl