A220547 - cp's OEIS frontend

A220547 Number of ways to reciprocally link elements of an n X 2 array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor.

n	a(n)
1	2
2	8
3	29
4	108
5	401
6	1490
7	5536
8	20569
9	76424
10	283953
11	1055026
12	3919944
13	14564533
14	54114452
15	201061985
16	747044834
17	2775641472
18	10312882481
19	38317465040
20	142368356257
21	528968939938
22	1965381541064
23	7302365621709
24	27131904192124

[2, 8, 29, 108, 401, 1490, 5536, 20569, 76424, 283953, 1055026, 3919944, 14564533, 54114452, 201061985, 747044834, 2775641472, 10312882481, 38317465040, 142368356257, 528968939938, 1965381541064, 7302365621709, 27131904192124]

cp's OEIS Frontend

A220547 Number of ways to reciprocally link elements of an n X 2 array either to themselves or to exactly one horizontal, vertical or antidiagonal neighbor.

Table of values

List of values