We compute the number of all rhombus tilings of a hexagon with sides a, b q 1, c, a q 1, b, c q 1, of which the central triangle is removed, provided a, b, c , where B β£ , β€, β₯ is the number of plane partitions inside the β£ = β€ = β₯ box. The proof uses nonintersecting lattice paths and a new identit
The Number of Centered Lozenge Tilings of a Symmetric Hexagon
β Scribed by M Ciucu; C Krattenthaler
- Publisher
- Elsevier Science
- Year
- 1999
- Tongue
- English
- Weight
- 257 KB
- Volume
- 86
- Category
- Article
- ISSN
- 0097-3165
No coin nor oath required. For personal study only.
β¦ Synopsis
Propp conjectured that the number of lozenge tilings of a semiregular hexagon of sides 2n&1, 2n&1, and 2n which contain the central unit rhombus is precisely one third of the total number of lozenge tilings. Motivated by this, we consider the more general situation of a semiregular hexagon of sides a, a, and b. We prove explicit formulas for the number of lozenge tilings of these hexagons containing the central unit rhombus and obtain Propp's conjecture as a corollary of our results.
π SIMILAR VOLUMES
We compute the number of rhombus tilings of a hexagon with side lengths a, b, c, a, b, c which contain the central rhombus and the number of rhombus tilings of a hexagon with side lengths a, b, c, a, b, c which contain the ``almost central'' rhombus above the centre.
## Abstract Mature B cells, upon activation, progressively differentiate through centroblasts into centrocytes and finally to plasmacytes that express large amounts of selected immunoglobulins. A significant part of this maturation is thought to involve induction of the unfolded protein response (U