Factorization in pure Rust

A natively cross-platform and fast factorization utility written in pure Rust.

Goals

• Support output in Math format (e.g. 2^3 * 3^2), core-utils format (e.g. 2 2 2 3 3), json format ({factors: {2:3, 3:2}, complete: true, residue: nil }).
• Support output diagnosis information to stderr (such as total time, expected time)
• Support parallel factorization (enable by default for integers larger than u64?)
• Support set timeout (for large target), and report the partial result (unfactorized part will be marked)
• Main benchmark: coreutils/factor (C), uutils/factor (uu_factor crate), primefac (Python), Pari/GP, SageMath, YAFU, Cado-NFS