|
|
A006725
|
|
Number of n-celled polygons with perimeter 2n+2 on square lattice.
(Formerly M1623)
|
|
3
|
|
|
1, 2, 6, 18, 55, 174, 566, 1868, 6237, 21050, 71666, 245696, 847317, 2937116, 10226574, 35746292, 125380257, 441125966, 1556301578, 18155586993
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
REFERENCES
|
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
LINKS
|
Table of n, a(n) for n=1..20.
I. G. Enting and A. J. Guttmann, On the area of square lattice polygons, J. Statist. Phys., 58 (1990), 475-484.
|
|
CROSSREFS
|
Sequence in context: A238236 A294159 A000778 * A066158 A148456 A148457
Adjacent sequences: A006722 A006723 A006724 * A006726 A006727 A006728
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
N. J. A. Sloane, Simon Plouffe
|
|
EXTENSIONS
|
Title corrected by David Bevan, Sep 28 2011
|
|
STATUS
|
approved
|
|
|
|