A239087 - cp's OEIS frontend

A239087 The sequence S = a(1), a(2), ... is defined by a(1)=1, if d,e,f are consecutive digits then we do not have d > e < f, and S is always extended with the smallest integer not yet present in S.

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

[1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 21, 13, 22, 23, 31, 14, 32, 24, 33, 34, 41, 15, 42, 25, 43, 35, 44, 45, 51, 16, 52, 26, 53, 36, 54, 46, 55, 56, 61, 17, 62, 27, 63, 37, 64, 47, 65, 57, 66, 67, 71, 18, 72, 28, 73, 38, 74, 48, 75, 58, 76, 68, 77, 78, 81, 19, 82, 29, 83, 39, 84, 49, 85, 59, 86, 69, 87, 79, 88, 89]

cp's OEIS Frontend

A239087 The sequence S = a(1), a(2), ... is defined by a(1)=1, if d,e,f are consecutive digits then we do not have d > e < f, and S is always extended with the smallest integer not yet present in S.

Table of values

List of values

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

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

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