A121635 - cp's OEIS frontend

A121635 Number of deco polyominoes of height n, having no 2-cell columns starting at level 0. A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.

n	a(n)
1	1
2	1
3	2
4	8
5	42
6	264
7	1920
8	15840
9	146160
10	1491840
11	16692480
12	203212800
13	2674425600
14	37841126400
15	572885913600
16	9240898867200
17	158228598528000
18	2866422214656000
19	54775863926784000
20	1101208277385216000
21	23234214178086912000
22	513342323725271040000

[1, 1, 2, 8, 42, 264, 1920, 15840, 146160, 1491840, 16692480, 203212800, 2674425600, 37841126400, 572885913600, 9240898867200, 158228598528000, 2866422214656000, 54775863926784000, 1101208277385216000, 23234214178086912000, 513342323725271040000]

cp's OEIS Frontend

A121635 Number of deco polyominoes of height n, having no 2-cell columns starting at level 0. A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.

Table of values

List of values