A056473 - cp's OEIS frontend

A056473 Number of palindromic structures using exactly four different symbols.

n	a(n)
1	0
2	0
3	0
4	0
5	0
6	0
7	1
8	1
9	10
10	10
11	65
12	65
13	350
14	350
15	1701
16	1701
17	7770
18	7770
19	34105
20	34105
21	145750
22	145750
23	611501
24	611501
25	2532530
26	2532530
27	10391745
28	10391745
29	42355950
30	42355950
31	171798901

[0, 0, 0, 0, 0, 0, 1, 1, 10, 10, 65, 65, 350, 350, 1701, 1701, 7770, 7770, 34105, 34105, 145750, 145750, 611501, 611501, 2532530, 2532530, 10391745, 10391745, 42355950, 42355950, 171798901]

cp's OEIS Frontend

A056473 Number of palindromic structures using exactly four different symbols.

Table of values

List of values