A239968 - cp's OEIS frontend

A239968 a(n) = 0 unless n is a nonprime A018252(k) then a(n) = k.

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

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

cp's OEIS Frontend

A239968 a(n) = 0 unless n is a nonprime A018252(k) then a(n) = k.

Table of values

List of values

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

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

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