A173021 - cp's OEIS frontend

A173021 Number of numbers <= n whose binary representation is without isolated ones or isolated double ones.

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	1
6	1
7	2
8	2
9	2
10	2
11	2
12	2
13	2
14	3
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	4
24	4
25	4
26	4
27	4
28	5
29	5
30	6
31	7
32	7
33	7
34	7
35	7
36	7
37	7
38	7
39	7
40	7
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	7
54	7
55	7
56	8
57	8
58	8
59	8
60	9
61	9
62	10
63	11
64	11
65	11
66	11
67	11
68	11
69	11
70	11
71	11
72	11
73	11
74	11
75	11
76	11
77	11
78	11
79	11
80	11
81	11
82	11
83	11
84	11
85	11
86	11
87	11
88	11
89	11

[1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11]

cp's OEIS Frontend

A173021 Number of numbers <= n whose binary representation is without isolated ones or isolated double ones.

Table of values

List of values

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	1
6	1
7	2
8	2
9	2
10	2
11	2
12	2
13	2
14	3
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	4
24	4
25	4
26	4
27	4
28	5
29	5
30	6
31	7
32	7
33	7
34	7
35	7
36	7
37	7
38	7
39	7
40	7
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	7
54	7
55	7
56	8
57	8
58	8
59	8
60	9
61	9
62	10
63	11
64	11
65	11
66	11
67	11
68	11
69	11
70	11
71	11
72	11
73	11
74	11
75	11
76	11
77	11
78	11
79	11
80	11
81	11
82	11
83	11
84	11
85	11
86	11
87	11
88	11
89	11

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	1
6	1
7	2
8	2
9	2
10	2
11	2
12	2
13	2
14	3
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	4
24	4
25	4
26	4
27	4
28	5
29	5
30	6
31	7
32	7
33	7
34	7
35	7
36	7
37	7
38	7
39	7
40	7
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	7
54	7
55	7
56	8
57	8
58	8
59	8
60	9
61	9
62	10
63	11
64	11
65	11
66	11
67	11
68	11
69	11
70	11
71	11
72	11
73	11
74	11
75	11
76	11
77	11
78	11
79	11
80	11
81	11
82	11
83	11
84	11
85	11
86	11
87	11
88	11
89	11

n	a(n)
0	1
1	1
2	1
3	1
4	1
5	1
6	1
7	2
8	2
9	2
10	2
11	2
12	2
13	2
14	3
15	4
16	4
17	4
18	4
19	4
20	4
21	4
22	4
23	4
24	4
25	4
26	4
27	4
28	5
29	5
30	6
31	7
32	7
33	7
34	7
35	7
36	7
37	7
38	7
39	7
40	7
41	7
42	7
43	7
44	7
45	7
46	7
47	7
48	7
49	7
50	7
51	7
52	7
53	7
54	7
55	7
56	8
57	8
58	8
59	8
60	9
61	9
62	10
63	11
64	11
65	11
66	11
67	11
68	11
69	11
70	11
71	11
72	11
73	11
74	11
75	11
76	11
77	11
78	11
79	11
80	11
81	11
82	11
83	11
84	11
85	11
86	11
87	11
88	11
89	11