A050026 - cp's OEIS frontend

A050026 a(n) = a(n-1) + a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = a(3) = 1.

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	10
12	11
13	13
14	16
15	20
16	25
17	31
18	32
19	33
20	34
21	36
22	39
23	43
24	48
25	54
26	62
27	71
28	81
29	92
30	105
31	121
32	141
33	166
34	167
35	168
36	169
37	171
38	174
39	178
40	183
41	189
42	197
43	206
44	216
45	227
46	240
47	256
48	276
49	301

[1, 1, 1, 2, 3, 4, 5, 6, 8, 9, 10, 11, 13, 16, 20, 25, 31, 32, 33, 34, 36, 39, 43, 48, 54, 62, 71, 81, 92, 105, 121, 141, 166, 167, 168, 169, 171, 174, 178, 183, 189, 197, 206, 216, 227, 240, 256, 276, 301]

cp's OEIS Frontend

A050026 a(n) = a(n-1) + a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = a(3) = 1.

Table of values

List of values

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	10
12	11
13	13
14	16
15	20
16	25
17	31
18	32
19	33
20	34
21	36
22	39
23	43
24	48
25	54
26	62
27	71
28	81
29	92
30	105
31	121
32	141
33	166
34	167
35	168
36	169
37	171
38	174
39	178
40	183
41	189
42	197
43	206
44	216
45	227
46	240
47	256
48	276
49	301

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	10
12	11
13	13
14	16
15	20
16	25
17	31
18	32
19	33
20	34
21	36
22	39
23	43
24	48
25	54
26	62
27	71
28	81
29	92
30	105
31	121
32	141
33	166
34	167
35	168
36	169
37	171
38	174
39	178
40	183
41	189
42	197
43	206
44	216
45	227
46	240
47	256
48	276
49	301

n	a(n)
1	1
2	1
3	1
4	2
5	3
6	4
7	5
8	6
9	8
10	9
11	10
12	11
13	13
14	16
15	20
16	25
17	31
18	32
19	33
20	34
21	36
22	39
23	43
24	48
25	54
26	62
27	71
28	81
29	92
30	105
31	121
32	141
33	166
34	167
35	168
36	169
37	171
38	174
39	178
40	183
41	189
42	197
43	206
44	216
45	227
46	240
47	256
48	276
49	301