A335924 - cp's OEIS frontend

A335924 A variation on Recamán's sequence (A005132): a(0) = 0, a(n) = a(n-1) - n if nonnegative and not already in the sequence; otherwise, a(n) = a(n-1) + ceiling(n/2) if not already in the sequence and a(n) = a(n-1) + n if already in the sequence.

n	a(n)
0	0
1	1
2	2
3	4
4	6
5	9
6	3
7	7
8	11
9	16
10	21
11	10
12	22
13	29
14	15
15	23
16	31
17	14
18	32
19	13
20	33
21	12
22	34
23	46
24	58
25	71
26	45
27	18
28	46
29	17
30	47
31	63
32	79
33	96
34	62
35	27
36	63
37	26
38	64
39	25
40	65
41	24
42	66
43	88
44	44
45	67
46	90
47	43
48	91
49	42
50	92
51	41
52	93
53	40
54	94
55	39
56	95
57	38
58	96
59	37
60	97
61	36
62	98
63	35
64	99
65	132
66	165

[0, 1, 2, 4, 6, 9, 3, 7, 11, 16, 21, 10, 22, 29, 15, 23, 31, 14, 32, 13, 33, 12, 34, 46, 58, 71, 45, 18, 46, 17, 47, 63, 79, 96, 62, 27, 63, 26, 64, 25, 65, 24, 66, 88, 44, 67, 90, 43, 91, 42, 92, 41, 93, 40, 94, 39, 95, 38, 96, 37, 97, 36, 98, 35, 99, 132, 165]

cp's OEIS Frontend

A335924 A variation on Recamán's sequence (A005132): a(0) = 0, a(n) = a(n-1) - n if nonnegative and not already in the sequence; otherwise, a(n) = a(n-1) + ceiling(n/2) if not already in the sequence and a(n) = a(n-1) + n if already in the sequence.

Table of values

List of values

n	a(n)
0	0
1	1
2	2
3	4
4	6
5	9
6	3
7	7
8	11
9	16
10	21
11	10
12	22
13	29
14	15
15	23
16	31
17	14
18	32
19	13
20	33
21	12
22	34
23	46
24	58
25	71
26	45
27	18
28	46
29	17
30	47
31	63
32	79
33	96
34	62
35	27
36	63
37	26
38	64
39	25
40	65
41	24
42	66
43	88
44	44
45	67
46	90
47	43
48	91
49	42
50	92
51	41
52	93
53	40
54	94
55	39
56	95
57	38
58	96
59	37
60	97
61	36
62	98
63	35
64	99
65	132
66	165

n	a(n)
0	0
1	1
2	2
3	4
4	6
5	9
6	3
7	7
8	11
9	16
10	21
11	10
12	22
13	29
14	15
15	23
16	31
17	14
18	32
19	13
20	33
21	12
22	34
23	46
24	58
25	71
26	45
27	18
28	46
29	17
30	47
31	63
32	79
33	96
34	62
35	27
36	63
37	26
38	64
39	25
40	65
41	24
42	66
43	88
44	44
45	67
46	90
47	43
48	91
49	42
50	92
51	41
52	93
53	40
54	94
55	39
56	95
57	38
58	96
59	37
60	97
61	36
62	98
63	35
64	99
65	132
66	165

n	a(n)
0	0
1	1
2	2
3	4
4	6
5	9
6	3
7	7
8	11
9	16
10	21
11	10
12	22
13	29
14	15
15	23
16	31
17	14
18	32
19	13
20	33
21	12
22	34
23	46
24	58
25	71
26	45
27	18
28	46
29	17
30	47
31	63
32	79
33	96
34	62
35	27
36	63
37	26
38	64
39	25
40	65
41	24
42	66
43	88
44	44
45	67
46	90
47	43
48	91
49	42
50	92
51	41
52	93
53	40
54	94
55	39
56	95
57	38
58	96
59	37
60	97
61	36
62	98
63	35
64	99
65	132
66	165