A191598 - cp's OEIS frontend

A191598 a(1)=1. Then, if the first n terms contain all the numbers 1 to n, a(n+1)=2*a(n), otherwise a(n+1) is the smallest number not already in the sequence.

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	10
8	7
9	8
10	9
11	18
12	11
13	12
14	13
15	14
16	15
17	16
18	17
19	34
20	19
21	20
22	21
23	22
24	23
25	24
26	25
27	26
28	27
29	28
30	29
31	30
32	31
33	32
34	33
35	66
36	35
37	36
38	37
39	38
40	39
41	40
42	41
43	42
44	43
45	44
46	45
47	46
48	47
49	48
50	49
51	50
52	51
53	52
54	53
55	54
56	55
57	56
58	57
59	58
60	59
61	60
62	61
63	62
64	63
65	64
66	65
67	130

[1, 2, 4, 3, 6, 5, 10, 7, 8, 9, 18, 11, 12, 13, 14, 15, 16, 17, 34, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 66, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 130]

cp's OEIS Frontend

A191598 a(1)=1. Then, if the first n terms contain all the numbers 1 to n, a(n+1)=2*a(n), otherwise a(n+1) is the smallest number not already in the sequence.

Table of values

List of values

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	10
8	7
9	8
10	9
11	18
12	11
13	12
14	13
15	14
16	15
17	16
18	17
19	34
20	19
21	20
22	21
23	22
24	23
25	24
26	25
27	26
28	27
29	28
30	29
31	30
32	31
33	32
34	33
35	66
36	35
37	36
38	37
39	38
40	39
41	40
42	41
43	42
44	43
45	44
46	45
47	46
48	47
49	48
50	49
51	50
52	51
53	52
54	53
55	54
56	55
57	56
58	57
59	58
60	59
61	60
62	61
63	62
64	63
65	64
66	65
67	130

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	10
8	7
9	8
10	9
11	18
12	11
13	12
14	13
15	14
16	15
17	16
18	17
19	34
20	19
21	20
22	21
23	22
24	23
25	24
26	25
27	26
28	27
29	28
30	29
31	30
32	31
33	32
34	33
35	66
36	35
37	36
38	37
39	38
40	39
41	40
42	41
43	42
44	43
45	44
46	45
47	46
48	47
49	48
50	49
51	50
52	51
53	52
54	53
55	54
56	55
57	56
58	57
59	58
60	59
61	60
62	61
63	62
64	63
65	64
66	65
67	130

n	a(n)
1	1
2	2
3	4
4	3
5	6
6	5
7	10
8	7
9	8
10	9
11	18
12	11
13	12
14	13
15	14
16	15
17	16
18	17
19	34
20	19
21	20
22	21
23	22
24	23
25	24
26	25
27	26
28	27
29	28
30	29
31	30
32	31
33	32
34	33
35	66
36	35
37	36
38	37
39	38
40	39
41	40
42	41
43	42
44	43
45	44
46	45
47	46
48	47
49	48
50	49
51	50
52	51
53	52
54	53
55	54
56	55
57	56
58	57
59	58
60	59
61	60
62	61
63	62
64	63
65	64
66	65
67	130