A386947 - cp's OEIS frontend

A386947 A variant of Recamán's sequence (A005132): a(0) = 0; for n > 0, a(n) = a(n-1) - n if nonnegative and not already in the sequence, otherwise a(n) = a(n-1) + n + 2.

n	a(n)
0	0
1	3
2	1
3	6
4	2
5	9
6	17
7	10
8	20
9	11
10	23
11	12
12	26
13	13
14	29
15	14
16	32
17	15
18	35
19	16
20	38
21	61
22	39
23	64
24	40
25	67
26	41
27	70
28	42
29	73
30	43
31	76
32	44
33	79
34	45
35	82
36	46
37	85
38	47
39	8
40	50
41	93
42	51
43	96
44	52
45	7
46	55
47	104
48	56
49	107
50	57
51	110
52	58
53	5
54	61
55	118
56	62
57	121
58	63
59	4
60	66

[0, 3, 1, 6, 2, 9, 17, 10, 20, 11, 23, 12, 26, 13, 29, 14, 32, 15, 35, 16, 38, 61, 39, 64, 40, 67, 41, 70, 42, 73, 43, 76, 44, 79, 45, 82, 46, 85, 47, 8, 50, 93, 51, 96, 52, 7, 55, 104, 56, 107, 57, 110, 58, 5, 61, 118, 62, 121, 63, 4, 66]

cp's OEIS Frontend

A386947 A variant of Recamán's sequence (A005132): a(0) = 0; for n > 0, a(n) = a(n-1) - n if nonnegative and not already in the sequence, otherwise a(n) = a(n-1) + n + 2.

Table of values

List of values

n	a(n)
0	0
1	3
2	1
3	6
4	2
5	9
6	17
7	10
8	20
9	11
10	23
11	12
12	26
13	13
14	29
15	14
16	32
17	15
18	35
19	16
20	38
21	61
22	39
23	64
24	40
25	67
26	41
27	70
28	42
29	73
30	43
31	76
32	44
33	79
34	45
35	82
36	46
37	85
38	47
39	8
40	50
41	93
42	51
43	96
44	52
45	7
46	55
47	104
48	56
49	107
50	57
51	110
52	58
53	5
54	61
55	118
56	62
57	121
58	63
59	4
60	66

n	a(n)
0	0
1	3
2	1
3	6
4	2
5	9
6	17
7	10
8	20
9	11
10	23
11	12
12	26
13	13
14	29
15	14
16	32
17	15
18	35
19	16
20	38
21	61
22	39
23	64
24	40
25	67
26	41
27	70
28	42
29	73
30	43
31	76
32	44
33	79
34	45
35	82
36	46
37	85
38	47
39	8
40	50
41	93
42	51
43	96
44	52
45	7
46	55
47	104
48	56
49	107
50	57
51	110
52	58
53	5
54	61
55	118
56	62
57	121
58	63
59	4
60	66

n	a(n)
0	0
1	3
2	1
3	6
4	2
5	9
6	17
7	10
8	20
9	11
10	23
11	12
12	26
13	13
14	29
15	14
16	32
17	15
18	35
19	16
20	38
21	61
22	39
23	64
24	40
25	67
26	41
27	70
28	42
29	73
30	43
31	76
32	44
33	79
34	45
35	82
36	46
37	85
38	47
39	8
40	50
41	93
42	51
43	96
44	52
45	7
46	55
47	104
48	56
49	107
50	57
51	110
52	58
53	5
54	61
55	118
56	62
57	121
58	63
59	4
60	66