A381406 - cp's OEIS frontend

A381406 a(0) = 0; for n > 0, a(n) is the smallest unused number such that a(n) OR a(n-1) = 2^k - 1, where OR is the binary OR operation and k>=1, while the binary weight of a(n) does not equal that of a(n-1).

n	a(n)
0	0
1	1
2	3
3	2
4	5
5	7
6	4
7	11
8	6
9	13
10	10
11	15
12	8
13	23
14	9
15	14
16	17
17	30
18	19
19	12
20	27
21	20
22	31
23	16
24	47
25	18
26	29
27	22
28	43
29	21
30	46
31	25
32	39
33	24
34	55
35	26
36	45
37	50
38	61
39	34
40	63
41	28
42	51
43	44
44	59
45	36
46	91
47	37
48	58
49	69
50	62
51	33
52	94
53	35
54	60
55	67
56	124
57	71
58	56
59	79
60	48
61	95
62	32
63	127
64	38
65	57
66	70
67	121
68	54
69	41
70	86
71	107
72	52
73	75
74	117
75	42
76	53
77	74
78	119
79	40
80	87
81	104
82	151
83	105
84	118
85	73
86	126
87	49
88	78
89	115

[0, 1, 3, 2, 5, 7, 4, 11, 6, 13, 10, 15, 8, 23, 9, 14, 17, 30, 19, 12, 27, 20, 31, 16, 47, 18, 29, 22, 43, 21, 46, 25, 39, 24, 55, 26, 45, 50, 61, 34, 63, 28, 51, 44, 59, 36, 91, 37, 58, 69, 62, 33, 94, 35, 60, 67, 124, 71, 56, 79, 48, 95, 32, 127, 38, 57, 70, 121, 54, 41, 86, 107, 52, 75, 117, 42, 53, 74, 119, 40, 87, 104, 151, 105, 118, 73, 126, 49, 78, 115]

cp's OEIS Frontend

A381406 a(0) = 0; for n > 0, a(n) is the smallest unused number such that a(n) OR a(n-1) = 2^k - 1, where OR is the binary OR operation and k>=1, while the binary weight of a(n) does not equal that of a(n-1).

Table of values

List of values

n	a(n)
0	0
1	1
2	3
3	2
4	5
5	7
6	4
7	11
8	6
9	13
10	10
11	15
12	8
13	23
14	9
15	14
16	17
17	30
18	19
19	12
20	27
21	20
22	31
23	16
24	47
25	18
26	29
27	22
28	43
29	21
30	46
31	25
32	39
33	24
34	55
35	26
36	45
37	50
38	61
39	34
40	63
41	28
42	51
43	44
44	59
45	36
46	91
47	37
48	58
49	69
50	62
51	33
52	94
53	35
54	60
55	67
56	124
57	71
58	56
59	79
60	48
61	95
62	32
63	127
64	38
65	57
66	70
67	121
68	54
69	41
70	86
71	107
72	52
73	75
74	117
75	42
76	53
77	74
78	119
79	40
80	87
81	104
82	151
83	105
84	118
85	73
86	126
87	49
88	78
89	115

n	a(n)
0	0
1	1
2	3
3	2
4	5
5	7
6	4
7	11
8	6
9	13
10	10
11	15
12	8
13	23
14	9
15	14
16	17
17	30
18	19
19	12
20	27
21	20
22	31
23	16
24	47
25	18
26	29
27	22
28	43
29	21
30	46
31	25
32	39
33	24
34	55
35	26
36	45
37	50
38	61
39	34
40	63
41	28
42	51
43	44
44	59
45	36
46	91
47	37
48	58
49	69
50	62
51	33
52	94
53	35
54	60
55	67
56	124
57	71
58	56
59	79
60	48
61	95
62	32
63	127
64	38
65	57
66	70
67	121
68	54
69	41
70	86
71	107
72	52
73	75
74	117
75	42
76	53
77	74
78	119
79	40
80	87
81	104
82	151
83	105
84	118
85	73
86	126
87	49
88	78
89	115

n	a(n)
0	0
1	1
2	3
3	2
4	5
5	7
6	4
7	11
8	6
9	13
10	10
11	15
12	8
13	23
14	9
15	14
16	17
17	30
18	19
19	12
20	27
21	20
22	31
23	16
24	47
25	18
26	29
27	22
28	43
29	21
30	46
31	25
32	39
33	24
34	55
35	26
36	45
37	50
38	61
39	34
40	63
41	28
42	51
43	44
44	59
45	36
46	91
47	37
48	58
49	69
50	62
51	33
52	94
53	35
54	60
55	67
56	124
57	71
58	56
59	79
60	48
61	95
62	32
63	127
64	38
65	57
66	70
67	121
68	54
69	41
70	86
71	107
72	52
73	75
74	117
75	42
76	53
77	74
78	119
79	40
80	87
81	104
82	151
83	105
84	118
85	73
86	126
87	49
88	78
89	115