A Generalized Arc-Consistency Algorithm for a Class of Counting   Constraints: Revised Edition that Incorporates One Correction
  This paper introduces the SEQ BIN meta-constraint with a polytime algorithm achieving general- ized arc-consistency according to some properties. SEQ BIN can be used for encoding counting con- straints such as CHANGE, SMOOTH or INCREAS- ING NVALUE. For some of these constraints and some of their variants GAC can be enforced with a time and space complexity linear in the sum of domain sizes, which improves or equals the best known results of the literature. 
Thierry Petit, Nicolas Beldiceanu and Xavier Lorca
cs.AI