Faster backtracking algorithms for the generation of symmetry-invariant permutations
Abstract
A new backtracking algorithm is developed for generating classes of permutations, that are invariant under the groupG4of rigid motions of the square generated by reflections about the horizontal and vertical axes. Special cases give a new algorithm for generating solutions of the classicaln-queens problem, as well as a new algorithm for generating Costas sequences, which are used in encoding radar and sonar signals. Parallel implementations of this latter algorithm have yielded new Costas sequences for lengthn,19≤n≤24.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 01, 2002
- Source ID
- 10.1155/s1110757x02203022
Entities
People
- Dorothy Bollman
- Edusmildo Orozco
- John Ramírez
- Oscar Moreno
Organizations
- City University of New York
- Office of Naval Research
- University of Puerto Rico