A230773 - cp's OEIS frontend

A230773 Minimum number of steps in an alternate definition of the Sieve of Eratosthenes needed to identify n as prime or composite.

n	a(n)
1	0
2	0
3	1
4	1
5	1
6	1
7	1
8	1
9	2
10	1
11	2
12	1
13	2
14	1
15	2
16	1
17	2
18	1
19	2
20	1
21	2
22	1
23	2
24	1
25	3
26	1
27	2
28	1
29	3
30	1
31	3
32	1
33	2
34	1
35	3
36	1
37	3
38	1
39	2
40	1
41	3
42	1
43	3
44	1
45	2
46	1
47	3
48	1
49	4
50	1
51	2
52	1
53	4
54	1
55	3
56	1
57	2
58	1
59	4
60	1
61	4
62	1
63	2
64	1
65	3
66	1
67	4
68	1
69	2
70	1
71	4
72	1
73	4
74	1
75	2
76	1
77	4
78	1
79	4
80	1
81	2
82	1
83	4
84	1
85	3
86	1
87	2

[0, 0, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 3, 1, 2, 1, 3, 1, 3, 1, 2, 1, 3, 1, 3, 1, 2, 1, 3, 1, 3, 1, 2, 1, 3, 1, 4, 1, 2, 1, 4, 1, 3, 1, 2, 1, 4, 1, 4, 1, 2, 1, 3, 1, 4, 1, 2, 1, 4, 1, 4, 1, 2, 1, 4, 1, 4, 1, 2, 1, 4, 1, 3, 1, 2]

cp's OEIS Frontend

A230773 Minimum number of steps in an alternate definition of the Sieve of Eratosthenes needed to identify n as prime or composite.

Table of values

List of values

n	a(n)
1	0
2	0
3	1
4	1
5	1
6	1
7	1
8	1
9	2
10	1
11	2
12	1
13	2
14	1
15	2
16	1
17	2
18	1
19	2
20	1
21	2
22	1
23	2
24	1
25	3
26	1
27	2
28	1
29	3
30	1
31	3
32	1
33	2
34	1
35	3
36	1
37	3
38	1
39	2
40	1
41	3
42	1
43	3
44	1
45	2
46	1
47	3
48	1
49	4
50	1
51	2
52	1
53	4
54	1
55	3
56	1
57	2
58	1
59	4
60	1
61	4
62	1
63	2
64	1
65	3
66	1
67	4
68	1
69	2
70	1
71	4
72	1
73	4
74	1
75	2
76	1
77	4
78	1
79	4
80	1
81	2
82	1
83	4
84	1
85	3
86	1
87	2

n	a(n)
1	0
2	0
3	1
4	1
5	1
6	1
7	1
8	1
9	2
10	1
11	2
12	1
13	2
14	1
15	2
16	1
17	2
18	1
19	2
20	1
21	2
22	1
23	2
24	1
25	3
26	1
27	2
28	1
29	3
30	1
31	3
32	1
33	2
34	1
35	3
36	1
37	3
38	1
39	2
40	1
41	3
42	1
43	3
44	1
45	2
46	1
47	3
48	1
49	4
50	1
51	2
52	1
53	4
54	1
55	3
56	1
57	2
58	1
59	4
60	1
61	4
62	1
63	2
64	1
65	3
66	1
67	4
68	1
69	2
70	1
71	4
72	1
73	4
74	1
75	2
76	1
77	4
78	1
79	4
80	1
81	2
82	1
83	4
84	1
85	3
86	1
87	2

n	a(n)
1	0
2	0
3	1
4	1
5	1
6	1
7	1
8	1
9	2
10	1
11	2
12	1
13	2
14	1
15	2
16	1
17	2
18	1
19	2
20	1
21	2
22	1
23	2
24	1
25	3
26	1
27	2
28	1
29	3
30	1
31	3
32	1
33	2
34	1
35	3
36	1
37	3
38	1
39	2
40	1
41	3
42	1
43	3
44	1
45	2
46	1
47	3
48	1
49	4
50	1
51	2
52	1
53	4
54	1
55	3
56	1
57	2
58	1
59	4
60	1
61	4
62	1
63	2
64	1
65	3
66	1
67	4
68	1
69	2
70	1
71	4
72	1
73	4
74	1
75	2
76	1
77	4
78	1
79	4
80	1
81	2
82	1
83	4
84	1
85	3
86	1
87	2