Mirrored from Sudopedia, the Free Sudoku Reference Guide
Candidates are equivalent when they must both be true or false at the same time.
Equivalence is an essential part of coloring. It allows us to use groups of candidates in logic reasoning, rather than individual candidates.
Players use parity marks or colors to track equivalence. Candidates with the same parity or color are equivalent. Candidates with different parity are opposite, as long as they belong to the same cluster.This page was last modified 19:59, 27 September 2007.