Complex sentence: In practice, we would test N-1 for small factors and obtain a factored part A and an unfactored part B, where all the factors of B are unknown, and would be greater than those of A.
Split into simpler sentences: In practice, we would test N-1 for small factors. We would obtain a factored part A and an unfactored part B, where all the factors of B are unknown, and would be greater than those of A.