A130911 - cp's OEIS frontend

A130911 a(n) is the number of primes with odd binary weight among the first n primes minus the number with an even binary weight.

n	a(n)
1	1
2	0
3	-1
4	0
5	1
6	2
7	1
8	2
9	1
10	0
11	1
12	2
13	3
14	2
15	3
16	2
17	3
18	4
19	5
20	4
21	5
22	6
23	5
24	4
25	5
26	4
27	5
28	6
29	7
30	6
31	7
32	8
33	9
34	8
35	7
36	8
37	9
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	13
46	14
47	15
48	16
49	17
50	18
51	19
52	20
53	21
54	22
55	21
56	20
57	19
58	20
59	19
60	18
61	19
62	18
63	19
64	18
65	19
66	18
67	19
68	18
69	17
70	16
71	15
72	14
73	15
74	14
75	15
76	14
77	13
78	14
79	13
80	14
81	15
82	16
83	17
84	18
85	19
86	20
87	19
88	20
89	19
90	20
91	19
92	18
93	19
94	20
95	21
96	20
97	19

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

cp's OEIS Frontend

A130911 a(n) is the number of primes with odd binary weight among the first n primes minus the number with an even binary weight.

Table of values

List of values

n	a(n)
1	1
2	0
3	-1
4	0
5	1
6	2
7	1
8	2
9	1
10	0
11	1
12	2
13	3
14	2
15	3
16	2
17	3
18	4
19	5
20	4
21	5
22	6
23	5
24	4
25	5
26	4
27	5
28	6
29	7
30	6
31	7
32	8
33	9
34	8
35	7
36	8
37	9
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	13
46	14
47	15
48	16
49	17
50	18
51	19
52	20
53	21
54	22
55	21
56	20
57	19
58	20
59	19
60	18
61	19
62	18
63	19
64	18
65	19
66	18
67	19
68	18
69	17
70	16
71	15
72	14
73	15
74	14
75	15
76	14
77	13
78	14
79	13
80	14
81	15
82	16
83	17
84	18
85	19
86	20
87	19
88	20
89	19
90	20
91	19
92	18
93	19
94	20
95	21
96	20
97	19

n	a(n)
1	1
2	0
3	-1
4	0
5	1
6	2
7	1
8	2
9	1
10	0
11	1
12	2
13	3
14	2
15	3
16	2
17	3
18	4
19	5
20	4
21	5
22	6
23	5
24	4
25	5
26	4
27	5
28	6
29	7
30	6
31	7
32	8
33	9
34	8
35	7
36	8
37	9
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	13
46	14
47	15
48	16
49	17
50	18
51	19
52	20
53	21
54	22
55	21
56	20
57	19
58	20
59	19
60	18
61	19
62	18
63	19
64	18
65	19
66	18
67	19
68	18
69	17
70	16
71	15
72	14
73	15
74	14
75	15
76	14
77	13
78	14
79	13
80	14
81	15
82	16
83	17
84	18
85	19
86	20
87	19
88	20
89	19
90	20
91	19
92	18
93	19
94	20
95	21
96	20
97	19

n	a(n)
1	1
2	0
3	-1
4	0
5	1
6	2
7	1
8	2
9	1
10	0
11	1
12	2
13	3
14	2
15	3
16	2
17	3
18	4
19	5
20	4
21	5
22	6
23	5
24	4
25	5
26	4
27	5
28	6
29	7
30	6
31	7
32	8
33	9
34	8
35	7
36	8
37	9
38	8
39	9
40	10
41	11
42	12
43	13
44	14
45	13
46	14
47	15
48	16
49	17
50	18
51	19
52	20
53	21
54	22
55	21
56	20
57	19
58	20
59	19
60	18
61	19
62	18
63	19
64	18
65	19
66	18
67	19
68	18
69	17
70	16
71	15
72	14
73	15
74	14
75	15
76	14
77	13
78	14
79	13
80	14
81	15
82	16
83	17
84	18
85	19
86	20
87	19
88	20
89	19
90	20
91	19
92	18
93	19
94	20
95	21
96	20
97	19