

A316198


Number of selfavoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set 0, +Pi/4, +Pi/2, +3*Pi/4, not counting rotations and reflections as distinct.


6




OFFSET

1,2


COMMENTS

Holes are excluded, i.e., the boundary path may nowhere touch or intersect itself.


LINKS

Table of n, a(n) for n=1..6.
Contest Organizers, Al Zimmermann's Programming Contests  Snakes on a Plane, Fall 2006.
Hugo Pfoertner, Illustration of polygons of perimeter <= 10.


CROSSREFS

Cf. A306178, A316195, A316197.
Sequence in context: A209459 A209521 A132525 * A074167 A083787 A138286
Adjacent sequences: A316195 A316196 A316197 * A316199 A316200 A316201


KEYWORD

nonn,walk,more


AUTHOR

Hugo Pfoertner, Jul 04 2018


STATUS

approved



