A348672 - cp's OEIS frontend

A348672 The numbers visited on a square spiral when stepping to the closest unvisited number such that the sum of that number and the current number is prime. If two or more such numbers exist then the smallest is chosen.

n	a(n)
1	1
2	2
3	3
4	4
5	15
6	14
7	33
8	34
9	13
10	30
11	29
12	12
13	11
14	8
15	9
16	10
17	27
18	26
19	47
20	24
21	23
22	6
23	5
24	18
25	19
26	40
27	39
28	68
29	69
30	70
31	43
32	108
33	71
34	42
35	41
36	20
37	21
38	22
39	7
40	46
41	25
42	48
43	49
44	52
45	51
46	50
47	81
48	82
49	169
50	168
51	221
52	222
53	167
54	164
55	117
56	116
57	77
58	114
59	113
60	44
61	45
62	112
63	111
64	158
65	159
66	214
67	277
68	280
69	351
70	350
71	281

[1, 2, 3, 4, 15, 14, 33, 34, 13, 30, 29, 12, 11, 8, 9, 10, 27, 26, 47, 24, 23, 6, 5, 18, 19, 40, 39, 68, 69, 70, 43, 108, 71, 42, 41, 20, 21, 22, 7, 46, 25, 48, 49, 52, 51, 50, 81, 82, 169, 168, 221, 222, 167, 164, 117, 116, 77, 114, 113, 44, 45, 112, 111, 158, 159, 214, 277, 280, 351, 350, 281]

cp's OEIS Frontend

A348672 The numbers visited on a square spiral when stepping to the closest unvisited number such that the sum of that number and the current number is prime. If two or more such numbers exist then the smallest is chosen.

Table of values

List of values

n	a(n)
1	1
2	2
3	3
4	4
5	15
6	14
7	33
8	34
9	13
10	30
11	29
12	12
13	11
14	8
15	9
16	10
17	27
18	26
19	47
20	24
21	23
22	6
23	5
24	18
25	19
26	40
27	39
28	68
29	69
30	70
31	43
32	108
33	71
34	42
35	41
36	20
37	21
38	22
39	7
40	46
41	25
42	48
43	49
44	52
45	51
46	50
47	81
48	82
49	169
50	168
51	221
52	222
53	167
54	164
55	117
56	116
57	77
58	114
59	113
60	44
61	45
62	112
63	111
64	158
65	159
66	214
67	277
68	280
69	351
70	350
71	281

n	a(n)
1	1
2	2
3	3
4	4
5	15
6	14
7	33
8	34
9	13
10	30
11	29
12	12
13	11
14	8
15	9
16	10
17	27
18	26
19	47
20	24
21	23
22	6
23	5
24	18
25	19
26	40
27	39
28	68
29	69
30	70
31	43
32	108
33	71
34	42
35	41
36	20
37	21
38	22
39	7
40	46
41	25
42	48
43	49
44	52
45	51
46	50
47	81
48	82
49	169
50	168
51	221
52	222
53	167
54	164
55	117
56	116
57	77
58	114
59	113
60	44
61	45
62	112
63	111
64	158
65	159
66	214
67	277
68	280
69	351
70	350
71	281

n	a(n)
1	1
2	2
3	3
4	4
5	15
6	14
7	33
8	34
9	13
10	30
11	29
12	12
13	11
14	8
15	9
16	10
17	27
18	26
19	47
20	24
21	23
22	6
23	5
24	18
25	19
26	40
27	39
28	68
29	69
30	70
31	43
32	108
33	71
34	42
35	41
36	20
37	21
38	22
39	7
40	46
41	25
42	48
43	49
44	52
45	51
46	50
47	81
48	82
49	169
50	168
51	221
52	222
53	167
54	164
55	117
56	116
57	77
58	114
59	113
60	44
61	45
62	112
63	111
64	158
65	159
66	214
67	277
68	280
69	351
70	350
71	281