A381419 - cp's OEIS frontend

A381419 a(1) = 1; for n > 1, a(n) is the smallest unused positive number that is coprime to a(n-1) and has a different binary weight than a(n-1).

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	9
11	13
12	10
13	19
14	12
15	23
16	14
17	15
18	16
19	17
20	21
21	20
22	27
23	22
24	29
25	18
26	25
27	24
28	31
29	26
30	33
31	28
32	39
33	32
34	35
35	34
36	37
37	30
38	41
39	36
40	43
41	38
42	45
43	44
44	47
45	40
46	49
47	46
48	55
49	42
50	53
51	48
52	59
53	50
54	51
55	52
56	57
57	56
58	61
59	54
60	65
61	58
62	63
63	62
64	67
65	60
66	73
67	64
68	69
69	68
70	71
71	66
72	79
73	70
74	83

[1, 3, 2, 5, 4, 7, 6, 11, 8, 9, 13, 10, 19, 12, 23, 14, 15, 16, 17, 21, 20, 27, 22, 29, 18, 25, 24, 31, 26, 33, 28, 39, 32, 35, 34, 37, 30, 41, 36, 43, 38, 45, 44, 47, 40, 49, 46, 55, 42, 53, 48, 59, 50, 51, 52, 57, 56, 61, 54, 65, 58, 63, 62, 67, 60, 73, 64, 69, 68, 71, 66, 79, 70, 83]

cp's OEIS Frontend

A381419 a(1) = 1; for n > 1, a(n) is the smallest unused positive number that is coprime to a(n-1) and has a different binary weight than a(n-1).

Table of values

List of values

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	9
11	13
12	10
13	19
14	12
15	23
16	14
17	15
18	16
19	17
20	21
21	20
22	27
23	22
24	29
25	18
26	25
27	24
28	31
29	26
30	33
31	28
32	39
33	32
34	35
35	34
36	37
37	30
38	41
39	36
40	43
41	38
42	45
43	44
44	47
45	40
46	49
47	46
48	55
49	42
50	53
51	48
52	59
53	50
54	51
55	52
56	57
57	56
58	61
59	54
60	65
61	58
62	63
63	62
64	67
65	60
66	73
67	64
68	69
69	68
70	71
71	66
72	79
73	70
74	83

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	9
11	13
12	10
13	19
14	12
15	23
16	14
17	15
18	16
19	17
20	21
21	20
22	27
23	22
24	29
25	18
26	25
27	24
28	31
29	26
30	33
31	28
32	39
33	32
34	35
35	34
36	37
37	30
38	41
39	36
40	43
41	38
42	45
43	44
44	47
45	40
46	49
47	46
48	55
49	42
50	53
51	48
52	59
53	50
54	51
55	52
56	57
57	56
58	61
59	54
60	65
61	58
62	63
63	62
64	67
65	60
66	73
67	64
68	69
69	68
70	71
71	66
72	79
73	70
74	83

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	9
11	13
12	10
13	19
14	12
15	23
16	14
17	15
18	16
19	17
20	21
21	20
22	27
23	22
24	29
25	18
26	25
27	24
28	31
29	26
30	33
31	28
32	39
33	32
34	35
35	34
36	37
37	30
38	41
39	36
40	43
41	38
42	45
43	44
44	47
45	40
46	49
47	46
48	55
49	42
50	53
51	48
52	59
53	50
54	51
55	52
56	57
57	56
58	61
59	54
60	65
61	58
62	63
63	62
64	67
65	60
66	73
67	64
68	69
69	68
70	71
71	66
72	79
73	70
74	83