A305974 - cp's OEIS frontend

A305974 a(1) = 1; for n > 1, if n = p^k for some prime p and exponent k >= 1, then a(n) = -k, otherwise a(n) = 1+A085970(n).

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

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

cp's OEIS Frontend

A305974 a(1) = 1; for n > 1, if n = p^k for some prime p and exponent k >= 1, then a(n) = -k, otherwise a(n) = 1+A085970(n).

Table of values

List of values

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

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

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