A111453 - cp's OEIS frontend

A111453 a(1)=1; for n>1, a(n) is smallest positive integer not occurring earlier in the sequence such that |a(n)-a(n-1)| is composite.

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

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

cp's OEIS Frontend

A111453 a(1)=1; for n>1, a(n) is smallest positive integer not occurring earlier in the sequence such that |a(n)-a(n-1)| is composite.

Table of values

List of values

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

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

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