A241917 - cp's OEIS frontend

A241917 If n is a prime with index i, p_i, a(n) = i, (with a(1)=0), otherwise difference (i-j) of the indices of the two largest primes p_i, p_j, i >= j in the prime factorization of n: a(n) = A061395(n) - A061395(A052126(n)).

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

[0, 1, 2, 0, 3, 1, 4, 0, 0, 2, 5, 1, 6, 3, 1, 0, 7, 0, 8, 2, 2, 4, 9, 1, 0, 5, 0, 3, 10, 1, 11, 0, 3, 6, 1, 0, 12, 7, 4, 2, 13, 2, 14, 4, 1, 8, 15, 1, 0, 0, 5, 5, 16, 0, 2, 3, 6, 9, 17, 1, 18, 10, 2, 0, 3, 3, 19, 6, 7, 1, 20, 0, 21, 11, 0, 7, 1, 4, 22, 2, 0, 12, 23]

cp's OEIS Frontend

A241917 If n is a prime with index i, p_i, a(n) = i, (with a(1)=0), otherwise difference (i-j) of the indices of the two largest primes p_i, p_j, i >= j in the prime factorization of n: a(n) = A061395(n) - A061395(A052126(n)).

Table of values

List of values

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

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

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