A377091 - cp's OEIS frontend

A377091 a(0) = 0; thereafter a(n) is the least integer (in absolute value) not yet in the sequence such that the absolute difference between a(n-1) and a(n) is a square; in case of a tie, preference is given to the positive value.

n	a(n)
0	0
1	1
2	2
3	-2
4	-1
5	3
6	4
7	5
8	-4
9	-3
10	6
11	7
12	8
13	-8
14	-7
15	-6
16	-5
17	-9
18	-10
19	-11
20	-12
21	13
22	9
23	10
24	11
25	12
26	-13
27	-14
28	-15
29	-16
30	-17
31	-18
32	18
33	14
34	15
35	16
36	17
37	-19
38	-20
39	-21
40	-22
41	-23
42	-24
43	25
44	21
45	20
46	19
47	23
48	22
49	26
50	27
51	28
52	24
53	-25
54	-26
55	-27
56	-28
57	-29
58	-30
59	-31
60	-32
61	32

[0, 1, 2, -2, -1, 3, 4, 5, -4, -3, 6, 7, 8, -8, -7, -6, -5, -9, -10, -11, -12, 13, 9, 10, 11, 12, -13, -14, -15, -16, -17, -18, 18, 14, 15, 16, 17, -19, -20, -21, -22, -23, -24, 25, 21, 20, 19, 23, 22, 26, 27, 28, 24, -25, -26, -27, -28, -29, -30, -31, -32, 32]

cp's OEIS Frontend

A377091 a(0) = 0; thereafter a(n) is the least integer (in absolute value) not yet in the sequence such that the absolute difference between a(n-1) and a(n) is a square; in case of a tie, preference is given to the positive value.

Table of values

List of values

n	a(n)
0	0
1	1
2	2
3	-2
4	-1
5	3
6	4
7	5
8	-4
9	-3
10	6
11	7
12	8
13	-8
14	-7
15	-6
16	-5
17	-9
18	-10
19	-11
20	-12
21	13
22	9
23	10
24	11
25	12
26	-13
27	-14
28	-15
29	-16
30	-17
31	-18
32	18
33	14
34	15
35	16
36	17
37	-19
38	-20
39	-21
40	-22
41	-23
42	-24
43	25
44	21
45	20
46	19
47	23
48	22
49	26
50	27
51	28
52	24
53	-25
54	-26
55	-27
56	-28
57	-29
58	-30
59	-31
60	-32
61	32

n	a(n)
0	0
1	1
2	2
3	-2
4	-1
5	3
6	4
7	5
8	-4
9	-3
10	6
11	7
12	8
13	-8
14	-7
15	-6
16	-5
17	-9
18	-10
19	-11
20	-12
21	13
22	9
23	10
24	11
25	12
26	-13
27	-14
28	-15
29	-16
30	-17
31	-18
32	18
33	14
34	15
35	16
36	17
37	-19
38	-20
39	-21
40	-22
41	-23
42	-24
43	25
44	21
45	20
46	19
47	23
48	22
49	26
50	27
51	28
52	24
53	-25
54	-26
55	-27
56	-28
57	-29
58	-30
59	-31
60	-32
61	32

n	a(n)
0	0
1	1
2	2
3	-2
4	-1
5	3
6	4
7	5
8	-4
9	-3
10	6
11	7
12	8
13	-8
14	-7
15	-6
16	-5
17	-9
18	-10
19	-11
20	-12
21	13
22	9
23	10
24	11
25	12
26	-13
27	-14
28	-15
29	-16
30	-17
31	-18
32	18
33	14
34	15
35	16
36	17
37	-19
38	-20
39	-21
40	-22
41	-23
42	-24
43	25
44	21
45	20
46	19
47	23
48	22
49	26
50	27
51	28
52	24
53	-25
54	-26
55	-27
56	-28
57	-29
58	-30
59	-31
60	-32
61	32