A111698 - cp's OEIS frontend

A111698 a(1)=1. Skipping over integers occurring earlier in the sequence, count down a composite from a(n) to get a(n+1) so that a(n+1) is the smallest possible positive integer arrived at this way. If there are no positive integers at a distance of a composite number of yet unused integers, instead count up from a(n) 4 (the lowest composite positive integer) positions (skipping already occurring integers) to get a(n+1).

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

[1, 5, 9, 2, 7, 12, 3, 10, 15, 4, 13, 18, 6, 16, 21, 8, 19, 24, 11, 22, 27, 14, 25, 30, 17, 28, 33, 20, 31, 36, 23, 34, 39, 26, 37, 42, 29, 40, 45, 32, 43, 48, 35, 46, 51, 38, 49, 54, 41, 52, 57, 44, 55, 60, 47, 58, 63, 50, 61, 66, 53, 64, 69, 56, 67, 72, 59, 70, 75, 62, 73, 78]

cp's OEIS Frontend

Table of values

List of values

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

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

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