A160649 - cp's OEIS frontend

A160649 a(1)=2. a(n) = a(n-1) + A001222(a(n-1)); where A001222(m) is the sum of prime-factorization exponents of m (or, A001222(m) is the number of primes dividing m, with multiplicity).

n	a(n)
1	2
2	3
3	4
4	6
5	8
6	11
7	12
8	15
9	17
10	18
11	21
12	23
13	24
14	28
15	31
16	32
17	37
18	38
19	40
20	44
21	47
22	48
23	53
24	54
25	58
26	60
27	64
28	70
29	73
30	74
31	76
32	79
33	80
34	85
35	87
36	89
37	90
38	94
39	96
40	102
41	105
42	108
43	113
44	114
45	117
46	120
47	125
48	128
49	135
50	139
51	140
52	144
53	150
54	154
55	157
56	158
57	160
58	166
59	168
60	173
61	174
62	177
63	179

[2, 3, 4, 6, 8, 11, 12, 15, 17, 18, 21, 23, 24, 28, 31, 32, 37, 38, 40, 44, 47, 48, 53, 54, 58, 60, 64, 70, 73, 74, 76, 79, 80, 85, 87, 89, 90, 94, 96, 102, 105, 108, 113, 114, 117, 120, 125, 128, 135, 139, 140, 144, 150, 154, 157, 158, 160, 166, 168, 173, 174, 177, 179]

cp's OEIS Frontend

A160649 a(1)=2. a(n) = a(n-1) + A001222(a(n-1)); where A001222(m) is the sum of prime-factorization exponents of m (or, A001222(m) is the number of primes dividing m, with multiplicity).

Table of values

List of values

n	a(n)
1	2
2	3
3	4
4	6
5	8
6	11
7	12
8	15
9	17
10	18
11	21
12	23
13	24
14	28
15	31
16	32
17	37
18	38
19	40
20	44
21	47
22	48
23	53
24	54
25	58
26	60
27	64
28	70
29	73
30	74
31	76
32	79
33	80
34	85
35	87
36	89
37	90
38	94
39	96
40	102
41	105
42	108
43	113
44	114
45	117
46	120
47	125
48	128
49	135
50	139
51	140
52	144
53	150
54	154
55	157
56	158
57	160
58	166
59	168
60	173
61	174
62	177
63	179

n	a(n)
1	2
2	3
3	4
4	6
5	8
6	11
7	12
8	15
9	17
10	18
11	21
12	23
13	24
14	28
15	31
16	32
17	37
18	38
19	40
20	44
21	47
22	48
23	53
24	54
25	58
26	60
27	64
28	70
29	73
30	74
31	76
32	79
33	80
34	85
35	87
36	89
37	90
38	94
39	96
40	102
41	105
42	108
43	113
44	114
45	117
46	120
47	125
48	128
49	135
50	139
51	140
52	144
53	150
54	154
55	157
56	158
57	160
58	166
59	168
60	173
61	174
62	177
63	179

n	a(n)
1	2
2	3
3	4
4	6
5	8
6	11
7	12
8	15
9	17
10	18
11	21
12	23
13	24
14	28
15	31
16	32
17	37
18	38
19	40
20	44
21	47
22	48
23	53
24	54
25	58
26	60
27	64
28	70
29	73
30	74
31	76
32	79
33	80
34	85
35	87
36	89
37	90
38	94
39	96
40	102
41	105
42	108
43	113
44	114
45	117
46	120
47	125
48	128
49	135
50	139
51	140
52	144
53	150
54	154
55	157
56	158
57	160
58	166
59	168
60	173
61	174
62	177
63	179