A353904 - cp's OEIS frontend

A353904 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 differs from a(n-1) at every digit.

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	13
11	9
12	14
13	23
14	10
15	21
16	16
17	25
18	12
19	29
20	15
21	22
22	17
23	20
24	19
25	24
26	31
27	18
28	35
29	26
30	33
31	28
32	37
33	40
34	27
35	32
36	41
37	30
38	43
39	34
40	45
41	38
42	47
43	36
44	49
45	51
46	44
47	39
48	46
49	53
50	42
51	55
52	48
53	59
54	61
55	50
56	63
57	52
58	67
59	54
60	65
61	56
62	69
63	58
64	71
65	57
66	62
67	73
68	60
69	77
70	64
71	75
72	68
73	79
74	66
75	83
76	70
77	81

[1, 3, 2, 5, 4, 7, 6, 11, 8, 13, 9, 14, 23, 10, 21, 16, 25, 12, 29, 15, 22, 17, 20, 19, 24, 31, 18, 35, 26, 33, 28, 37, 40, 27, 32, 41, 30, 43, 34, 45, 38, 47, 36, 49, 51, 44, 39, 46, 53, 42, 55, 48, 59, 61, 50, 63, 52, 67, 54, 65, 56, 69, 58, 71, 57, 62, 73, 60, 77, 64, 75, 68, 79, 66, 83, 70, 81]

cp's OEIS Frontend

A353904 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 differs from a(n-1) at every digit.

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	13
11	9
12	14
13	23
14	10
15	21
16	16
17	25
18	12
19	29
20	15
21	22
22	17
23	20
24	19
25	24
26	31
27	18
28	35
29	26
30	33
31	28
32	37
33	40
34	27
35	32
36	41
37	30
38	43
39	34
40	45
41	38
42	47
43	36
44	49
45	51
46	44
47	39
48	46
49	53
50	42
51	55
52	48
53	59
54	61
55	50
56	63
57	52
58	67
59	54
60	65
61	56
62	69
63	58
64	71
65	57
66	62
67	73
68	60
69	77
70	64
71	75
72	68
73	79
74	66
75	83
76	70
77	81

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	13
11	9
12	14
13	23
14	10
15	21
16	16
17	25
18	12
19	29
20	15
21	22
22	17
23	20
24	19
25	24
26	31
27	18
28	35
29	26
30	33
31	28
32	37
33	40
34	27
35	32
36	41
37	30
38	43
39	34
40	45
41	38
42	47
43	36
44	49
45	51
46	44
47	39
48	46
49	53
50	42
51	55
52	48
53	59
54	61
55	50
56	63
57	52
58	67
59	54
60	65
61	56
62	69
63	58
64	71
65	57
66	62
67	73
68	60
69	77
70	64
71	75
72	68
73	79
74	66
75	83
76	70
77	81

n	a(n)
1	1
2	3
3	2
4	5
5	4
6	7
7	6
8	11
9	8
10	13
11	9
12	14
13	23
14	10
15	21
16	16
17	25
18	12
19	29
20	15
21	22
22	17
23	20
24	19
25	24
26	31
27	18
28	35
29	26
30	33
31	28
32	37
33	40
34	27
35	32
36	41
37	30
38	43
39	34
40	45
41	38
42	47
43	36
44	49
45	51
46	44
47	39
48	46
49	53
50	42
51	55
52	48
53	59
54	61
55	50
56	63
57	52
58	67
59	54
60	65
61	56
62	69
63	58
64	71
65	57
66	62
67	73
68	60
69	77
70	64
71	75
72	68
73	79
74	66
75	83
76	70
77	81