

A320945


a(n) is the number of topperimeter tiles among all rhombic tilings of the 2ngon.


2




OFFSET

2,3


COMMENTS

Also the number of bottomperimeter tiles among all rhombic tilings of the 2ngon. Tiles and polygons all have sides of length 1, as in A006245.


LINKS

Table of n, a(n) for n=2..6.
B. E. Tenner, Tilingbased models of perimeter and area, arXiv:1811.00082 [math.CO], 2018.


EXAMPLE

a(4) = 3 because among the eight rhombic tilings of the octagon, 3 topperimeter rhombi appear.


CROSSREFS

Cf. A320944, A320946, A006245.
Sequence in context: A197975 A210906 A193194 * A166232 A136551 A266812
Adjacent sequences: A320942 A320943 A320944 * A320946 A320947 A320948


KEYWORD

nonn,more


AUTHOR

Bridget Tenner, Oct 24 2018


STATUS

approved



