Oriented Chains
From Sudopedia, the Free Sudoku Reference Guide
Jump to navigationJump to searchOriented Chains are generalisations of the basic xy-chains.
The central idea is that the information collected from previous candidates in a chain (and/or from the target) can be used to select the next candidates. Oriented chains are either 2D or 3D:
- oriented 2D chains: xyt-chains, xyz-chains and xyzt-chains, together with their "hidden" counterparts: hxyt-chains, hxyz-chains and hxyzt-chains;
- oriented 3D chains: nrct-chains, nrcz-chains, nrczt-chains.
The original reference to all these chains is the book "The Hidden Logic of Sudoku" by Denis Berthier.
