A051755 - cp's OEIS frontend

A051755 Consider problem of placing N queens on an n X n board so that each queen attacks precisely 2 others. Sequence gives maximal number of queens.

n	a(n)
2	3
3	4
4	6
5	8
6	10
7	12
8	14
9	16
10	18
11	20
12	22
13	24
14	26
15	28
16	30
17	32
18	34
19	36
20	38
21	40
22	42
23	44
24	46
25	48
26	50
27	52
28	54
29	56
30	58
31	60
32	62
33	64
34	66
35	68
36	70
37	72
38	74
39	76
40	78
41	80
42	82
43	84
44	86
45	88
46	90
47	92
48	94
49	96
50	98
51	100
52	102
53	104
54	106
55	108
56	110
57	112
58	114
59	116
60	118
61	120
62	122
63	124
64	126
65	128
66	130

[3, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84, 86, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 130]

cp's OEIS Frontend

A051755 Consider problem of placing N queens on an n X n board so that each queen attacks precisely 2 others. Sequence gives maximal number of queens.

Table of values

List of values

n	a(n)
2	3
3	4
4	6
5	8
6	10
7	12
8	14
9	16
10	18
11	20
12	22
13	24
14	26
15	28
16	30
17	32
18	34
19	36
20	38
21	40
22	42
23	44
24	46
25	48
26	50
27	52
28	54
29	56
30	58
31	60
32	62
33	64
34	66
35	68
36	70
37	72
38	74
39	76
40	78
41	80
42	82
43	84
44	86
45	88
46	90
47	92
48	94
49	96
50	98
51	100
52	102
53	104
54	106
55	108
56	110
57	112
58	114
59	116
60	118
61	120
62	122
63	124
64	126
65	128
66	130

n	a(n)
2	3
3	4
4	6
5	8
6	10
7	12
8	14
9	16
10	18
11	20
12	22
13	24
14	26
15	28
16	30
17	32
18	34
19	36
20	38
21	40
22	42
23	44
24	46
25	48
26	50
27	52
28	54
29	56
30	58
31	60
32	62
33	64
34	66
35	68
36	70
37	72
38	74
39	76
40	78
41	80
42	82
43	84
44	86
45	88
46	90
47	92
48	94
49	96
50	98
51	100
52	102
53	104
54	106
55	108
56	110
57	112
58	114
59	116
60	118
61	120
62	122
63	124
64	126
65	128
66	130

n	a(n)
2	3
3	4
4	6
5	8
6	10
7	12
8	14
9	16
10	18
11	20
12	22
13	24
14	26
15	28
16	30
17	32
18	34
19	36
20	38
21	40
22	42
23	44
24	46
25	48
26	50
27	52
28	54
29	56
30	58
31	60
32	62
33	64
34	66
35	68
36	70
37	72
38	74
39	76
40	78
41	80
42	82
43	84
44	86
45	88
46	90
47	92
48	94
49	96
50	98
51	100
52	102
53	104
54	106
55	108
56	110
57	112
58	114
59	116
60	118
61	120
62	122
63	124
64	126
65	128
66	130