A066246 - cp's OEIS frontend

A066246 a(n) = 0 unless n is a composite number A002808(k) then a(n) = k.

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

[0, 0, 0, 1, 0, 2, 0, 3, 4, 5, 0, 6, 0, 7, 8, 9, 0, 10, 0, 11, 12, 13, 0, 14, 15, 16, 17, 18, 0, 19, 0, 20, 21, 22, 23, 24, 0, 25, 26, 27, 0, 28, 0, 29, 30, 31, 0, 32, 33, 34, 35, 36, 0, 37, 38, 39, 40, 41, 0, 42, 0, 43, 44, 45, 46, 47, 0, 48, 49, 50, 0, 51, 0, 52, 53, 54, 55, 56, 0, 57]

cp's OEIS Frontend

A066246 a(n) = 0 unless n is a composite number A002808(k) then a(n) = k.

Table of values

List of values

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

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

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