A272573 - cp's OEIS frontend

A272573 Start a spiral of numbers on a hexagonal tiling, with the initial hexagon as a(1) = 1. a(n) is the smallest positive integer not equal to or previously adjacent to its neighbors.

n	a(n)
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	4
9	6
10	8
11	5
12	9
13	8
14	10
15	2
16	11
17	3
18	10
19	11
20	12
21	13
22	9
23	12
24	7
25	13
26	14
27	1
28	11
29	13
30	15
31	9
32	16
33	14
34	7
35	16
36	17
37	15
38	1
39	16
40	18
41	7
42	17
43	19
44	20
45	1
46	17
47	18
48	19
49	9
50	21
51	3
52	20
53	10
54	22
55	4
56	15
57	21
58	23
59	5
60	22
61	23
62	10
63	21
64	6
65	22
66	24
67	25
68	2
69	14
70	22
71	25
72	26
73	3

[1, 2, 3, 4, 5, 6, 7, 4, 6, 8, 5, 9, 8, 10, 2, 11, 3, 10, 11, 12, 13, 9, 12, 7, 13, 14, 1, 11, 13, 15, 9, 16, 14, 7, 16, 17, 15, 1, 16, 18, 7, 17, 19, 20, 1, 17, 18, 19, 9, 21, 3, 20, 10, 22, 4, 15, 21, 23, 5, 22, 23, 10, 21, 6, 22, 24, 25, 2, 14, 22, 25, 26, 3]

cp's OEIS Frontend

A272573 Start a spiral of numbers on a hexagonal tiling, with the initial hexagon as a(1) = 1. a(n) is the smallest positive integer not equal to or previously adjacent to its neighbors.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	4
9	6
10	8
11	5
12	9
13	8
14	10
15	2
16	11
17	3
18	10
19	11
20	12
21	13
22	9
23	12
24	7
25	13
26	14
27	1
28	11
29	13
30	15
31	9
32	16
33	14
34	7
35	16
36	17
37	15
38	1
39	16
40	18
41	7
42	17
43	19
44	20
45	1
46	17
47	18
48	19
49	9
50	21
51	3
52	20
53	10
54	22
55	4
56	15
57	21
58	23
59	5
60	22
61	23
62	10
63	21
64	6
65	22
66	24
67	25
68	2
69	14
70	22
71	25
72	26
73	3

n	a(n)
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	4
9	6
10	8
11	5
12	9
13	8
14	10
15	2
16	11
17	3
18	10
19	11
20	12
21	13
22	9
23	12
24	7
25	13
26	14
27	1
28	11
29	13
30	15
31	9
32	16
33	14
34	7
35	16
36	17
37	15
38	1
39	16
40	18
41	7
42	17
43	19
44	20
45	1
46	17
47	18
48	19
49	9
50	21
51	3
52	20
53	10
54	22
55	4
56	15
57	21
58	23
59	5
60	22
61	23
62	10
63	21
64	6
65	22
66	24
67	25
68	2
69	14
70	22
71	25
72	26
73	3

n	a(n)
1	1
2	2
3	3
4	4
5	5
6	6
7	7
8	4
9	6
10	8
11	5
12	9
13	8
14	10
15	2
16	11
17	3
18	10
19	11
20	12
21	13
22	9
23	12
24	7
25	13
26	14
27	1
28	11
29	13
30	15
31	9
32	16
33	14
34	7
35	16
36	17
37	15
38	1
39	16
40	18
41	7
42	17
43	19
44	20
45	1
46	17
47	18
48	19
49	9
50	21
51	3
52	20
53	10
54	22
55	4
56	15
57	21
58	23
59	5
60	22
61	23
62	10
63	21
64	6
65	22
66	24
67	25
68	2
69	14
70	22
71	25
72	26
73	3