A375890 - cp's OEIS frontend

A375890 a(1) = 1; for n > 1, a(n) is the smallest unused positive number such that a(n) is coprime to a(n-1) and (a(n) AND a(n-1)) = min(a(n), a(n-1)), where AND is the binary AND operation.

n	a(n)
1	1
2	3
3	2
4	7
5	4
6	5
7	13
8	8
9	9
10	11
11	10
12	27
13	16
14	17
15	19
16	18
17	23
18	6
19	31
20	12
21	29
22	20
23	21
24	53
25	32
26	33
27	35
28	34
29	39
30	37
31	36
32	47
33	14
34	15
35	79
36	64
37	65
38	67
39	66
40	71
41	68
42	69
43	77
44	72
45	73
46	75
47	74
48	91
49	24
50	25
51	57
52	40
53	41
54	43
55	42
56	59
57	26
58	63
59	22
60	87
61	70
62	103
63	38
64	55
65	48
66	49
67	51
68	50
69	119
70	52
71	61
72	28
73	93
74	76
75	109
76	44

[1, 3, 2, 7, 4, 5, 13, 8, 9, 11, 10, 27, 16, 17, 19, 18, 23, 6, 31, 12, 29, 20, 21, 53, 32, 33, 35, 34, 39, 37, 36, 47, 14, 15, 79, 64, 65, 67, 66, 71, 68, 69, 77, 72, 73, 75, 74, 91, 24, 25, 57, 40, 41, 43, 42, 59, 26, 63, 22, 87, 70, 103, 38, 55, 48, 49, 51, 50, 119, 52, 61, 28, 93, 76, 109, 44]

cp's OEIS Frontend

A375890 a(1) = 1; for n > 1, a(n) is the smallest unused positive number such that a(n) is coprime to a(n-1) and (a(n) AND a(n-1)) = min(a(n), a(n-1)), where AND is the binary AND operation.

Table of values

List of values

n	a(n)
1	1
2	3
3	2
4	7
5	4
6	5
7	13
8	8
9	9
10	11
11	10
12	27
13	16
14	17
15	19
16	18
17	23
18	6
19	31
20	12
21	29
22	20
23	21
24	53
25	32
26	33
27	35
28	34
29	39
30	37
31	36
32	47
33	14
34	15
35	79
36	64
37	65
38	67
39	66
40	71
41	68
42	69
43	77
44	72
45	73
46	75
47	74
48	91
49	24
50	25
51	57
52	40
53	41
54	43
55	42
56	59
57	26
58	63
59	22
60	87
61	70
62	103
63	38
64	55
65	48
66	49
67	51
68	50
69	119
70	52
71	61
72	28
73	93
74	76
75	109
76	44

n	a(n)
1	1
2	3
3	2
4	7
5	4
6	5
7	13
8	8
9	9
10	11
11	10
12	27
13	16
14	17
15	19
16	18
17	23
18	6
19	31
20	12
21	29
22	20
23	21
24	53
25	32
26	33
27	35
28	34
29	39
30	37
31	36
32	47
33	14
34	15
35	79
36	64
37	65
38	67
39	66
40	71
41	68
42	69
43	77
44	72
45	73
46	75
47	74
48	91
49	24
50	25
51	57
52	40
53	41
54	43
55	42
56	59
57	26
58	63
59	22
60	87
61	70
62	103
63	38
64	55
65	48
66	49
67	51
68	50
69	119
70	52
71	61
72	28
73	93
74	76
75	109
76	44

n	a(n)
1	1
2	3
3	2
4	7
5	4
6	5
7	13
8	8
9	9
10	11
11	10
12	27
13	16
14	17
15	19
16	18
17	23
18	6
19	31
20	12
21	29
22	20
23	21
24	53
25	32
26	33
27	35
28	34
29	39
30	37
31	36
32	47
33	14
34	15
35	79
36	64
37	65
38	67
39	66
40	71
41	68
42	69
43	77
44	72
45	73
46	75
47	74
48	91
49	24
50	25
51	57
52	40
53	41
54	43
55	42
56	59
57	26
58	63
59	22
60	87
61	70
62	103
63	38
64	55
65	48
66	49
67	51
68	50
69	119
70	52
71	61
72	28
73	93
74	76
75	109
76	44