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Table of n, a(n) for n=7..30.
A. J. Guttmann, Indicators of solvability for lattice models, Discrete Math., 217 (2000), 167-189 (H_7 for square lattices of Section 6).
Sequence in context: A056281 A000481 A215765 * A026859 A096046 A093117
Adjacent sequences: A055900 A055901 A055902 * A055904 A055905 A055906
Christian G. Bower, Jun 13 2000