An elementary proof is given for the number of convex polyominos of perimeter 2m =t 4. ## Let +4 denote the number of nonisomo perimeter 2m + 4, m 3 2. elest and Viennot olyominos with P h+4 = (2nr + 7)2ti-4 -4(2ne -3,(ZJ.
On the number of hexagonal polyominoes
✍ Scribed by Markus Vöge; Anthony J. Guttmann
- Publisher
- Elsevier Science
- Year
- 2003
- Tongue
- English
- Weight
- 570 KB
- Volume
- 307
- Category
- Article
- ISSN
- 0304-3975
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✦ Synopsis
A combination of the reÿned ÿnite lattice method and transfer matrices allows a radical increase in the computer enumeration of polyominoes on the hexagonal lattice (equivalently, site clusters on the triangular lattice), pn with n hexagons. We obtain pn for n 6 35. We prove that pn = n+o(n) , obtain the bounds 4:8049 6 6 5:9047, and estimate that =5:1831478(17). Finally, we provide compelling numerical evidence that the generating function pnz n ≈ A(z)log(1-z), for z → (1= ) -with A(z) holomorphic in a cut plane, estimate A(1= ) and predict the sub-leading asymptotic behaviour, identifying a non-analytic correction-to-scaling term with exponent =3=2. On the basis of universality and previous numerical work we argue that the mean-square radius of gyration R 2 g n of polyominoes of size n grows as n 2 , with = 0:64115(5).
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