Hexagon tilings of the plane that are not edge-to-edgeActa Mathematica Academiae Scientiarum Hungarica - Tập 164 - Trang 341-349 - 2021
D. Frettlöh, A. Glazyrin, Z. Lángi
An irregular vertex in a tiling by polygons is a vertex of one tile
and belongs to the interior of an edge of another tile. In this paper we show that
for any integer
$$k\geq 3$$
, there exists a normal tiling of the Euclidean plane by convex
hexagons of unit area with exactly
...... hiện toàn bộ
The sum of squares of degrees of bipartite graphsActa Mathematica Academiae Scientiarum Hungarica - Tập 171 - Trang 1-11 - 2023
M. G. Neubauer
Let G be a subgraph of the complete bipartite graph
$$K_{l,m},{l \leq m}$$
, with
$$e=qm+p>0$$
,
$$0 \leq p ... hiện toàn bộ
The Number of Compatible Totally Bounded Quasi-UniformitiesActa Mathematica Academiae Scientiarum Hungarica - Tập 88 - Trang 15-23 - 2000
H.-P. A. Künzi, M. J. Pérez-Peñalver
We prove that a topological space that admits a nontransitive totally bounded quasi-uniformity, admits at least
$$2^{2^{N_0 } } $$
nontransitive totally bounded quasi-uniformities. Furthermore we show that each infinite T
2-space admits at least
...... hiện toàn bộ