A252462 - cp's OEIS frontend

A252462 Shift one instance of the largest prime one step towards smaller primes: a(1) = 1, a(2^n) = 2^(n-1), and for other numbers: a(n) = (n / prime(g)) * prime(g-1), where g = A061395(n), index of the greatest prime dividing n.

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

[1, 1, 2, 2, 3, 4, 5, 4, 6, 6, 7, 8, 11, 10, 9, 8, 13, 12, 17, 12, 15, 14, 19, 16, 15, 22, 18, 20, 23, 18, 29, 16, 21, 26, 25, 24, 31, 34, 33, 24, 37, 30, 41, 28, 27, 38, 43, 32, 35, 30, 39, 44, 47, 36, 35, 40, 51, 46, 53, 36, 59, 58, 45, 32, 55, 42, 61, 52, 57, 50, 67, 48, 71, 62, 45, 68, 49, 66, 73, 48, 54, 74, 79, 60]

cp's OEIS Frontend

A252462 Shift one instance of the largest prime one step towards smaller primes: a(1) = 1, a(2^n) = 2^(n-1), and for other numbers: a(n) = (n / prime(g)) * prime(g-1), where g = A061395(n), index of the greatest prime dividing n.

Table of values

List of values

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

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

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