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A213451
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Number of fixed triangular strip polyedges with n edges.
(Formerly N1209)
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0
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3, 15, 69, 309, 1365, 5973, 25941, 112065, 482067, 2066583, 8834469, 37677603, 160367343
(list;
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refs;
listen;
history;
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OFFSET
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1,1
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REFERENCES
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N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
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LINKS
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Table of n, a(n) for n=1..13.
C. Domb, On the theory of cooperative phenomena in crystals, Advances in Phys., 9 (1960), 149-361. See page 354.
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FORMULA
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Apparently, a(n) = A001334(n)/2 for n >= 1. It needs to be clarified whether the objects described by this sequence are equivalent to the self-avoiding walks on the hexagonal lattice together with a restriction on their orientation. - Hugo Pfoertner, Jul 24 2021
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CROSSREFS
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Cf. A001334, A151540, A151541.
Sequence in context: A325586 A304276 A217451 * A224749 A122558 A110211
Adjacent sequences: A213448 A213449 A213450 * A213452 A213453 A213454
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KEYWORD
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nonn,more
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AUTHOR
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N. J. A. Sloane, Jun 11 2012
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EXTENSIONS
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Better description and more terms from Joseph Myers, Jun 12 2012
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STATUS
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approved
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