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On nonisomorphic Room squares


Authors: J. H. Dinitz and D. R. Stinson
Journal: Proc. Amer. Math. Soc. 89 (1983), 175-181
MSC: Primary 05B15
DOI: https://doi.org/10.1090/S0002-9939-1983-0706536-8
MathSciNet review: 706536
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Abstract: Let $ {\text{NR}}(s)$ denote the number of nonisomorphic Room squares of side $ s$. We prove that for $ s$ sufficiently large, $ {\text{NR}}(s) \geqslant \exp (c{s^2})$ for some absolute constant $ c$. More precisely, $ {\text{NR}}(s) \geqslant .19\exp (.04{s^2})$ for $ s \geqslant 153\;{\operatorname{odd}}$; and $ {\text{NR}}(s) \geqslant .19\exp (.09{s^2})$ for $ s \geqslant 1001{\text{ odd }}$.


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DOI: https://doi.org/10.1090/S0002-9939-1983-0706536-8
Article copyright: © Copyright 1983 American Mathematical Society

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