English

On a Problem Posed by Maurice Nivat

Combinatorics 2007-05-23 v1 Logic

Abstract

Consider a m×nm \times n matrix AA, whose elements are arbitrary integers. Consider, for each square window of size 2×22 \times 2, the sum of the corresponding elements of AA. These sums form a (m1)×(n1)(m - 1) \times (n-1) matrix SS. Can we efficiently (in polynomial time) restore the original matrix AA given SS? This problem was originally posed by Maurice Nivat for the case when the elements of matrix AA are zeros and ones. We prove that this problem is solvable in polynomial time. Moreover, the problem still can be efficiently solved if the elements of AA are integers from given intervals. On the other hand, for 2×32 \times 3 windows the similar problem turns out to be NP-complete.

Keywords

Cite

@article{arxiv.math/0609230,
  title  = {On a Problem Posed by Maurice Nivat},
  author = {Maxim A. Babenko},
  journal= {arXiv preprint arXiv:math/0609230},
  year   = {2007}
}

Comments

8 pages