A348761 - cp's OEIS frontend

A348761 For any nonnegative number n with binary expansion Sum_{k >= 0} b_k * 2^k, a(n) is the imaginary part of f(n) = Sum_{k >= 0} ((-1)^Sum_{j = 0..k-1} b_j) * (1+i)^k (where i denotes the imaginary unit); sequence A348760 gives the real part.

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

[0, 0, 1, -1, 2, -2, -1, 1, 2, -2, -1, 1, 0, 0, 1, -1, 0, 0, 1, -1, 2, -2, -1, 1, 2, -2, -1, 1, 0, 0, 1, -1, -4, 4, 5, -5, 6, -6, -5, 5, 6, -6, -5, 5, -4, 4, 5, -5, 4, -4, -3, 3, -2, 2, 3, -3, -2, 2, 3, -3, 4, -4, -3, 3, -8, 8, 9, -9, 10, -10, -9, 9, 10, -10]

cp's OEIS Frontend

A348761 For any nonnegative number n with binary expansion Sum_{k >= 0} b_k * 2^k, a(n) is the imaginary part of f(n) = Sum_{k >= 0} ((-1)^Sum_{j = 0..k-1} b_j) * (1+i)^k (where i denotes the imaginary unit); sequence A348760 gives the real part.

Table of values

List of values

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

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

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