We present a combinatorial solution to the problem of determining the number of lozenge tilings of a hexagon with sides a, b+1, b, a+1, b, b+1, with the central unit triangle removed. For a=b, this settles an open problem posed by Propp [7].
Enumeration of Lozenge Tilings of Hexagons with a Central Triangular Hole
✍ Scribed by M. Ciucu; T. Eisenkölbl; C. Krattenthaler; D. Zare
- Book ID
- 102970641
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 789 KB
- Volume
- 95
- Category
- Article
- ISSN
- 0097-3165
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✦ Synopsis
We deal with unweighted and weighted enumerations of lozenge tilings of a hexagon with side lengths a, b+m, c, a+m, b, c+m, where an equilateral triangle of side length m has been removed from the center. We give closed formulas for the plain enumeration and for a certain (&1)-enumeration of these lozenge tilings. In the case that a=b=c, we also provide closed formulas for certain weighted enumerations of those lozenge tilings that are cyclically symmetric. For m=0, the latter formulas specialize to statements about weighted enumerations of cyclically
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