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A213451 Number of fixed triangular strip polyedges with n edges.
(Formerly N1209)
0
3, 15, 69, 309, 1365, 5973, 25941, 112065, 482067, 2066583, 8834469, 37677603, 160367343 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
REFERENCES
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
LINKS
C. Domb, On the theory of cooperative phenomena in crystals, Advances in Phys., 9 (1960), 149-361. See page 354.
FORMULA
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
CROSSREFS
Sequence in context: A325586 A304276 A217451 * A224749 A122558 A110211
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Jun 11 2012
EXTENSIONS
Better description and more terms from Joseph Myers, Jun 12 2012
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)