A137217 - cp's OEIS frontend

A137217 A self-describing sequence: 2 odd digits between two even, then 3 odd digits between two even, then 5 odd digits between two even, then 6, then 7... The length of each run of odd digits is given by the sequence itself (the smallest available integer is used when needed). Zero is an even digit.

n	a(n)
1	2
2	3
3	5
4	6
5	7
6	9
7	10
8	11
9	13
10	14
11	15
12	17
13	19
14	21
15	31
16	33
17	35
18	41
19	51
20	53
21	55
22	57
23	61
24	71
25	73
26	75
27	77
28	78
29	79
30	91
31	93
32	95
33	97
34	98
35	99
36	111
37	113
38	115
39	116
40	117
41	119
42	131
43	133
44	134
45	135
46	137
47	139
48	151
49	153
50	211
51	311
52	313
53	315
54	317
55	319
56	411
57	511
58	513
59	515
60	517
61	519
62	530

[2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 19, 21, 31, 33, 35, 41, 51, 53, 55, 57, 61, 71, 73, 75, 77, 78, 79, 91, 93, 95, 97, 98, 99, 111, 113, 115, 116, 117, 119, 131, 133, 134, 135, 137, 139, 151, 153, 211, 311, 313, 315, 317, 319, 411, 511, 513, 515, 517, 519, 530]

cp's OEIS Frontend

Table of values

List of values

n	a(n)
1	2
2	3
3	5
4	6
5	7
6	9
7	10
8	11
9	13
10	14
11	15
12	17
13	19
14	21
15	31
16	33
17	35
18	41
19	51
20	53
21	55
22	57
23	61
24	71
25	73
26	75
27	77
28	78
29	79
30	91
31	93
32	95
33	97
34	98
35	99
36	111
37	113
38	115
39	116
40	117
41	119
42	131
43	133
44	134
45	135
46	137
47	139
48	151
49	153
50	211
51	311
52	313
53	315
54	317
55	319
56	411
57	511
58	513
59	515
60	517
61	519
62	530

n	a(n)
1	2
2	3
3	5
4	6
5	7
6	9
7	10
8	11
9	13
10	14
11	15
12	17
13	19
14	21
15	31
16	33
17	35
18	41
19	51
20	53
21	55
22	57
23	61
24	71
25	73
26	75
27	77
28	78
29	79
30	91
31	93
32	95
33	97
34	98
35	99
36	111
37	113
38	115
39	116
40	117
41	119
42	131
43	133
44	134
45	135
46	137
47	139
48	151
49	153
50	211
51	311
52	313
53	315
54	317
55	319
56	411
57	511
58	513
59	515
60	517
61	519
62	530

n	a(n)
1	2
2	3
3	5
4	6
5	7
6	9
7	10
8	11
9	13
10	14
11	15
12	17
13	19
14	21
15	31
16	33
17	35
18	41
19	51
20	53
21	55
22	57
23	61
24	71
25	73
26	75
27	77
28	78
29	79
30	91
31	93
32	95
33	97
34	98
35	99
36	111
37	113
38	115
39	116
40	117
41	119
42	131
43	133
44	134
45	135
46	137
47	139
48	151
49	153
50	211
51	311
52	313
53	315
54	317
55	319
56	411
57	511
58	513
59	515
60	517
61	519
62	530