A353990 - cp's OEIS frontend

A353990 a(1) = 1; for n > 1, a(n) is the smallest positive number that has not yet appeared that is coprime to a(n-1), does not equal a(n-1)+1, and whose binary expansion has no 1-bit in common with the binary expansion of a(n-1).

n	a(n)
1	1
2	4
3	3
4	8
5	5
6	2
7	9
8	16
9	7
10	24
11	35
12	12
13	17
14	6
15	25
16	32
17	11
18	20
19	33
20	10
21	21
22	34
23	13
24	18
25	37
26	26
27	69
28	40
29	19
30	36
31	65
32	14
33	81
34	38
35	73
36	22
37	41
38	64
39	15
40	112
41	129
42	28
43	67
44	44
45	83
46	128
47	23
48	72
49	49
50	66
51	29
52	96
53	31
54	160
55	27
56	68
57	43
58	80
59	39
60	88
61	131
62	48
63	71
64	56
65	135
66	104
67	133
68	50
69	77
70	130
71	53
72	74
73	145
74	42

[1, 4, 3, 8, 5, 2, 9, 16, 7, 24, 35, 12, 17, 6, 25, 32, 11, 20, 33, 10, 21, 34, 13, 18, 37, 26, 69, 40, 19, 36, 65, 14, 81, 38, 73, 22, 41, 64, 15, 112, 129, 28, 67, 44, 83, 128, 23, 72, 49, 66, 29, 96, 31, 160, 27, 68, 43, 80, 39, 88, 131, 48, 71, 56, 135, 104, 133, 50, 77, 130, 53, 74, 145, 42]

cp's OEIS Frontend

A353990 a(1) = 1; for n > 1, a(n) is the smallest positive number that has not yet appeared that is coprime to a(n-1), does not equal a(n-1)+1, and whose binary expansion has no 1-bit in common with the binary expansion of a(n-1).

Table of values

List of values

n	a(n)
1	1
2	4
3	3
4	8
5	5
6	2
7	9
8	16
9	7
10	24
11	35
12	12
13	17
14	6
15	25
16	32
17	11
18	20
19	33
20	10
21	21
22	34
23	13
24	18
25	37
26	26
27	69
28	40
29	19
30	36
31	65
32	14
33	81
34	38
35	73
36	22
37	41
38	64
39	15
40	112
41	129
42	28
43	67
44	44
45	83
46	128
47	23
48	72
49	49
50	66
51	29
52	96
53	31
54	160
55	27
56	68
57	43
58	80
59	39
60	88
61	131
62	48
63	71
64	56
65	135
66	104
67	133
68	50
69	77
70	130
71	53
72	74
73	145
74	42

n	a(n)
1	1
2	4
3	3
4	8
5	5
6	2
7	9
8	16
9	7
10	24
11	35
12	12
13	17
14	6
15	25
16	32
17	11
18	20
19	33
20	10
21	21
22	34
23	13
24	18
25	37
26	26
27	69
28	40
29	19
30	36
31	65
32	14
33	81
34	38
35	73
36	22
37	41
38	64
39	15
40	112
41	129
42	28
43	67
44	44
45	83
46	128
47	23
48	72
49	49
50	66
51	29
52	96
53	31
54	160
55	27
56	68
57	43
58	80
59	39
60	88
61	131
62	48
63	71
64	56
65	135
66	104
67	133
68	50
69	77
70	130
71	53
72	74
73	145
74	42

n	a(n)
1	1
2	4
3	3
4	8
5	5
6	2
7	9
8	16
9	7
10	24
11	35
12	12
13	17
14	6
15	25
16	32
17	11
18	20
19	33
20	10
21	21
22	34
23	13
24	18
25	37
26	26
27	69
28	40
29	19
30	36
31	65
32	14
33	81
34	38
35	73
36	22
37	41
38	64
39	15
40	112
41	129
42	28
43	67
44	44
45	83
46	128
47	23
48	72
49	49
50	66
51	29
52	96
53	31
54	160
55	27
56	68
57	43
58	80
59	39
60	88
61	131
62	48
63	71
64	56
65	135
66	104
67	133
68	50
69	77
70	130
71	53
72	74
73	145
74	42