A closed formula for the number of convex permutominoes.
A non graph theory approach to Ulam's conjecture
Achieving snaky.
Adding layers to bumped-body polyforms with minimum perimeter preserves minimum perimeter.
Asymptotically optimal box packing theorems.
Combinatorial approaches and conjectures for 2-divisibility problems concerning domino tilings of polyominoes.
Convex hulls of polyominoes.
Counting horizontally convex polyominoes.
Counting perfect matchings in polyominoes with an application to the dimer problem
Counting polyominoes on twisted cylinders.
Defect theorem in the plane
We consider the defect theorem in the context of labelled polyominoes, i.e., two-dimensional figures. The classical version of this property states that if a set of n words is not a code then the words can be expressed as a product of at most n - 1 words, the smaller set being a code. We survey several two-dimensional extensions exhibiting the boundaries where the theorem fails. In particular, we establish the defect property in the case of three dominoes (n × 1 or 1 × n rectangles).
Generating functions for directed animals convex following their direction.
Metastability of the three dimensional Ising model on a torus at very low temperatures.
n-tilability of acyclic polyominoes
On general dissections of a polygon.
On general dissections of a polygon. (Short Communication).
On multi-avoidance of right angled numbered polyomino patterns.
On the generation and enumeration of some classes of convex polyominoes.
On the permanents of certain circulant matrices and related Toeplitz matrices. (Über die Permanente gewisser zirkulanter Matrizen und damit zusammenhängender Toeplitz-Matrizen.)
On the sequence A079500 and its combinatorial interpretations.