A086283 - cp's OEIS frontend

A086283 a(1)=1, a(2)=1 and, for n>2, a(n) is the smallest positive integer such that the sequence of second order absolute difference is the sequence of positive integers {1,2,3,4,...}.

n	a(n)
1	1
2	1
3	2
4	5
5	5
6	1
7	10
8	7
9	17
10	15
11	4
12	3
13	15
14	15
15	2
16	29
17	17
18	45
19	34
20	5
21	15
22	45
23	36
24	5
25	13
26	45
27	38
28	5
29	11
30	45
31	40
32	5
33	1
34	37
35	34
36	71
37	69
38	31
39	30
40	69
41	69
42	29
43	110
44	71
45	153
46	27
47	108
48	73
49	155
50	25
51	106
52	75
53	157
54	23
55	104
56	77
57	159
58	21
59	102
60	79
61	161
62	19
63	100
64	81
65	163
66	17
67	98
68	83
69	1
70	15
71	98

[1, 1, 2, 5, 5, 1, 10, 7, 17, 15, 4, 3, 15, 15, 2, 29, 17, 45, 34, 5, 15, 45, 36, 5, 13, 45, 38, 5, 11, 45, 40, 5, 1, 37, 34, 71, 69, 31, 30, 69, 69, 29, 110, 71, 153, 27, 108, 73, 155, 25, 106, 75, 157, 23, 104, 77, 159, 21, 102, 79, 161, 19, 100, 81, 163, 17, 98, 83, 1, 15, 98]

cp's OEIS Frontend

A086283 a(1)=1, a(2)=1 and, for n>2, a(n) is the smallest positive integer such that the sequence of second order absolute difference is the sequence of positive integers {1,2,3,4,...}.

Table of values

List of values

n	a(n)
1	1
2	1
3	2
4	5
5	5
6	1
7	10
8	7
9	17
10	15
11	4
12	3
13	15
14	15
15	2
16	29
17	17
18	45
19	34
20	5
21	15
22	45
23	36
24	5
25	13
26	45
27	38
28	5
29	11
30	45
31	40
32	5
33	1
34	37
35	34
36	71
37	69
38	31
39	30
40	69
41	69
42	29
43	110
44	71
45	153
46	27
47	108
48	73
49	155
50	25
51	106
52	75
53	157
54	23
55	104
56	77
57	159
58	21
59	102
60	79
61	161
62	19
63	100
64	81
65	163
66	17
67	98
68	83
69	1
70	15
71	98

n	a(n)
1	1
2	1
3	2
4	5
5	5
6	1
7	10
8	7
9	17
10	15
11	4
12	3
13	15
14	15
15	2
16	29
17	17
18	45
19	34
20	5
21	15
22	45
23	36
24	5
25	13
26	45
27	38
28	5
29	11
30	45
31	40
32	5
33	1
34	37
35	34
36	71
37	69
38	31
39	30
40	69
41	69
42	29
43	110
44	71
45	153
46	27
47	108
48	73
49	155
50	25
51	106
52	75
53	157
54	23
55	104
56	77
57	159
58	21
59	102
60	79
61	161
62	19
63	100
64	81
65	163
66	17
67	98
68	83
69	1
70	15
71	98

n	a(n)
1	1
2	1
3	2
4	5
5	5
6	1
7	10
8	7
9	17
10	15
11	4
12	3
13	15
14	15
15	2
16	29
17	17
18	45
19	34
20	5
21	15
22	45
23	36
24	5
25	13
26	45
27	38
28	5
29	11
30	45
31	40
32	5
33	1
34	37
35	34
36	71
37	69
38	31
39	30
40	69
41	69
42	29
43	110
44	71
45	153
46	27
47	108
48	73
49	155
50	25
51	106
52	75
53	157
54	23
55	104
56	77
57	159
58	21
59	102
60	79
61	161
62	19
63	100
64	81
65	163
66	17
67	98
68	83
69	1
70	15
71	98