A208671 - cp's OEIS frontend

A208671 T(n,k) = number of 2n-bead necklaces labeled with numbers 1..k allowing reversal, with neighbors differing by exactly 1.

n	a(n)
1	0
2	1
3	0
4	2
5	1
6	0
7	3
8	3
9	1
10	0
11	4
12	5
13	4
14	1
15	0
16	5
17	7
18	8
19	6
20	1
21	0
22	6
23	9
24	12
25	14
26	8
27	1
28	0
29	7
30	11
31	16
32	23
33	24
34	13
35	1
36	0
37	8
38	13
39	20
40	32
41	44
42	47
43	18
44	1
45	0
46	9
47	15
48	24
49	41
50	65
51	97
52	89
53	30
54	1
55	0
56	10
57	17
58	28
59	50
60	86
61	152
62	212
63	187
64	46
65	1
66	0
67	11
68	19
69	32
70	59
71	107
72	208
73	360
74	512
75	396
76	78
77	1
78	0
79	12
80	21
81	36

[0, 1, 0, 2, 1, 0, 3, 3, 1, 0, 4, 5, 4, 1, 0, 5, 7, 8, 6, 1, 0, 6, 9, 12, 14, 8, 1, 0, 7, 11, 16, 23, 24, 13, 1, 0, 8, 13, 20, 32, 44, 47, 18, 1, 0, 9, 15, 24, 41, 65, 97, 89, 30, 1, 0, 10, 17, 28, 50, 86, 152, 212, 187, 46, 1, 0, 11, 19, 32, 59, 107, 208, 360, 512, 396, 78, 1, 0, 12, 21, 36]

cp's OEIS Frontend

A208671 T(n,k) = number of 2n-bead necklaces labeled with numbers 1..k allowing reversal, with neighbors differing by exactly 1.

Table of values

List of values

n	a(n)
1	0
2	1
3	0
4	2
5	1
6	0
7	3
8	3
9	1
10	0
11	4
12	5
13	4
14	1
15	0
16	5
17	7
18	8
19	6
20	1
21	0
22	6
23	9
24	12
25	14
26	8
27	1
28	0
29	7
30	11
31	16
32	23
33	24
34	13
35	1
36	0
37	8
38	13
39	20
40	32
41	44
42	47
43	18
44	1
45	0
46	9
47	15
48	24
49	41
50	65
51	97
52	89
53	30
54	1
55	0
56	10
57	17
58	28
59	50
60	86
61	152
62	212
63	187
64	46
65	1
66	0
67	11
68	19
69	32
70	59
71	107
72	208
73	360
74	512
75	396
76	78
77	1
78	0
79	12
80	21
81	36

n	a(n)
1	0
2	1
3	0
4	2
5	1
6	0
7	3
8	3
9	1
10	0
11	4
12	5
13	4
14	1
15	0
16	5
17	7
18	8
19	6
20	1
21	0
22	6
23	9
24	12
25	14
26	8
27	1
28	0
29	7
30	11
31	16
32	23
33	24
34	13
35	1
36	0
37	8
38	13
39	20
40	32
41	44
42	47
43	18
44	1
45	0
46	9
47	15
48	24
49	41
50	65
51	97
52	89
53	30
54	1
55	0
56	10
57	17
58	28
59	50
60	86
61	152
62	212
63	187
64	46
65	1
66	0
67	11
68	19
69	32
70	59
71	107
72	208
73	360
74	512
75	396
76	78
77	1
78	0
79	12
80	21
81	36

n	a(n)
1	0
2	1
3	0
4	2
5	1
6	0
7	3
8	3
9	1
10	0
11	4
12	5
13	4
14	1
15	0
16	5
17	7
18	8
19	6
20	1
21	0
22	6
23	9
24	12
25	14
26	8
27	1
28	0
29	7
30	11
31	16
32	23
33	24
34	13
35	1
36	0
37	8
38	13
39	20
40	32
41	44
42	47
43	18
44	1
45	0
46	9
47	15
48	24
49	41
50	65
51	97
52	89
53	30
54	1
55	0
56	10
57	17
58	28
59	50
60	86
61	152
62	212
63	187
64	46
65	1
66	0
67	11
68	19
69	32
70	59
71	107
72	208
73	360
74	512
75	396
76	78
77	1
78	0
79	12
80	21
81	36