In theory, if sha-1 were a "good" hash function in the sense of evenly distributed, then if there are 2^20 prefixes then each would get 1/2^20 fraction of all t

In theory, if sha-1 were a "good" hash function in the sense of evenly distributed, then if there are 2^20 prefixes then each would get 1/2^20 fraction of all the hashes.