3.7.64. Costas arrays

A constraint that allows for expressing the Costas arrays problem. A Costas array is a permutation p 1 ,p 2 ,...,p n of n integers 1,2,...,n such that ∀δ∈[1,n-2],∀i∈[1,n-δ-1],∀j∈[i+1,n-δ]:p i -p i+δ ≠p j -p j+δ . A. Vellino compares in  [Vellino90] three approaches respectively using Prolog, Pascal and CHIP for solving the Costas arrays problem.