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A266549 revision #30

A266549

Number of 2n-step 2-dimensional closed self-avoiding paths on square lattice, reduced for symmetry, i.e., where rotations and reflections are not counted as distinct.

0, 1, 1, 3, 6, 25, 86, 414, 1975, 10479, 56572, 316577, 1800363, 10419605, 61061169, 361978851

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,4

COMMENTS

Differs from A057730 beginning at n = 8, since that sequence includes polyominoes with holes.

LINKS

Table of n, a(n) for n=1..16.

Joerg Arndt, All a(6)=25 walks of length 12, 2018

Hugo Pfoertner, Illustration of ratio A002931(n)/a(n) using Plot2.

Hugo Pfoertner, Illustration of polygons of perimeter <= 16.

CROSSREFS