Smooth prime MD5 collisions

Ben Laurie ben at
Thu Oct 20 19:39:37 EDT 2005

Inspired by, I have just produced
this prime:


which I claim collides (using the well-known alternative block) with a
number that has the first 26 primes as factors.

Also, while I was writing this, I got:


which collides with 43 primes.

Code and stuff will follow, but now I'm going to bed. I expect its
obvious how they are made, anyway.




"There is no limit to what a man can do or how far he can go if he
doesn't mind who gets the credit." - Robert Woodruff

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