A316199 Number of self-avoiding polygons with perimeter 2*n and sides = 1 that have vertex angles from the set +-Pi/9, +-3*Pi/9, +-5*Pi/9, +-7*Pi/9, not counting rotations and reflections as distinct.

0, 0, 8, 17, 472, 7042

Offset: 1

Author

Hugo Pfoertner, Jul 04 2018

Keywords

• nonn
• walk
• more

Comments

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

Links

• Contest Organizers, Al Zimmermann's Programming Contests - Snakes on a Plane, Fall 2006.
• Hugo Pfoertner, Illustration of polygons of perimeter <= 12.

Crossrefs

Cf. A306179, A316195, A316197, A316198.