A080427 - cp's OEIS frontend

A080427 a(1)=1 and, for n>1, a(n) is the smallest positive integer such that the absolute difference |a(n)-a(n-1)| has not occurred previously.

n	a(n)
1	1
2	1
3	2
4	4
5	1
6	5
7	10
8	1
9	7
10	14
11	1
12	9
13	19
14	1
15	12
16	24
17	1
18	15
19	30
20	1
21	17
22	34
23	1
24	20
25	40
26	1
27	22
28	44
29	1
30	25
31	50
32	1
33	27
34	54
35	1
36	29
37	59
38	1
39	32
40	64
41	1
42	35
43	70
44	1
45	37
46	74
47	1
48	39
49	79
50	1
51	42
52	84
53	1
54	45
55	90
56	1
57	47
58	94
59	1
60	49
61	99
62	1
63	52
64	104
65	1
66	55
67	110
68	1
69	57
70	114
71	1
72	60
73	120
74	1
75	62
76	124
77	1
78	65
79	130

[1, 1, 2, 4, 1, 5, 10, 1, 7, 14, 1, 9, 19, 1, 12, 24, 1, 15, 30, 1, 17, 34, 1, 20, 40, 1, 22, 44, 1, 25, 50, 1, 27, 54, 1, 29, 59, 1, 32, 64, 1, 35, 70, 1, 37, 74, 1, 39, 79, 1, 42, 84, 1, 45, 90, 1, 47, 94, 1, 49, 99, 1, 52, 104, 1, 55, 110, 1, 57, 114, 1, 60, 120, 1, 62, 124, 1, 65, 130]

cp's OEIS Frontend

A080427 a(1)=1 and, for n>1, a(n) is the smallest positive integer such that the absolute difference |a(n)-a(n-1)| has not occurred previously.

Table of values

List of values

n	a(n)
1	1
2	1
3	2
4	4
5	1
6	5
7	10
8	1
9	7
10	14
11	1
12	9
13	19
14	1
15	12
16	24
17	1
18	15
19	30
20	1
21	17
22	34
23	1
24	20
25	40
26	1
27	22
28	44
29	1
30	25
31	50
32	1
33	27
34	54
35	1
36	29
37	59
38	1
39	32
40	64
41	1
42	35
43	70
44	1
45	37
46	74
47	1
48	39
49	79
50	1
51	42
52	84
53	1
54	45
55	90
56	1
57	47
58	94
59	1
60	49
61	99
62	1
63	52
64	104
65	1
66	55
67	110
68	1
69	57
70	114
71	1
72	60
73	120
74	1
75	62
76	124
77	1
78	65
79	130

n	a(n)
1	1
2	1
3	2
4	4
5	1
6	5
7	10
8	1
9	7
10	14
11	1
12	9
13	19
14	1
15	12
16	24
17	1
18	15
19	30
20	1
21	17
22	34
23	1
24	20
25	40
26	1
27	22
28	44
29	1
30	25
31	50
32	1
33	27
34	54
35	1
36	29
37	59
38	1
39	32
40	64
41	1
42	35
43	70
44	1
45	37
46	74
47	1
48	39
49	79
50	1
51	42
52	84
53	1
54	45
55	90
56	1
57	47
58	94
59	1
60	49
61	99
62	1
63	52
64	104
65	1
66	55
67	110
68	1
69	57
70	114
71	1
72	60
73	120
74	1
75	62
76	124
77	1
78	65
79	130

n	a(n)
1	1
2	1
3	2
4	4
5	1
6	5
7	10
8	1
9	7
10	14
11	1
12	9
13	19
14	1
15	12
16	24
17	1
18	15
19	30
20	1
21	17
22	34
23	1
24	20
25	40
26	1
27	22
28	44
29	1
30	25
31	50
32	1
33	27
34	54
35	1
36	29
37	59
38	1
39	32
40	64
41	1
42	35
43	70
44	1
45	37
46	74
47	1
48	39
49	79
50	1
51	42
52	84
53	1
54	45
55	90
56	1
57	47
58	94
59	1
60	49
61	99
62	1
63	52
64	104
65	1
66	55
67	110
68	1
69	57
70	114
71	1
72	60
73	120
74	1
75	62
76	124
77	1
78	65
79	130