Binary Nontiles

• Authors: Don Coppersmith;Victor S. Miller
• Venue: SIAM Journal on Discrete Mathematics
• Year: 2012

A subset $V \subseteq \mathbb{F}_2^n$ is a tile if $\mathbb{F}_2^n$ can be covered by disjoint translates of $V$. In other words, $V$ is a tile if and only if there is a subset $A \subseteq \mathbb{F}_2^n$ such that $V+A = \mathbb{F}_2^n$ uniquely (i.e., $v + a = v' + a'$ implies that $v=v'$ and $a=a'$, where $v,v' \in V$ and $a,a' \in A$). In some problems in coding theory and hashing we are given a putative tile $V$ and wish to know whether or not it is a tile. In this paper we give two computational criteria for certifying that $V$ is not a tile. The first involves the impossibility of a bin-packing problem, and the second involves the infeasibility of a linear program. We apply both criteria to a list of putative tiles given by Gordon, Miller, and Ostapenko [IEEE Trans. Inform. Theory, 56 (2010), pp. 984-991] in the context of hashing to find close matches, to show that none of them are, in fact, tiles.