A116626 - cp's OEIS frontend

A116626 a(1)=1; a(odd n) = a(n-1) XOR a(n-2), for a(even n) we find the first i > 1 such that neither i nor (i XOR A116626(n-1)) is present in A116626(1..n-1), in which case a(n) = (i XOR A116626(n-1)).

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	8
8	13
9	5
10	15
11	10
12	26
13	16
14	23
15	7
16	14
17	9
18	24
19	17
20	49
21	32
22	43
23	11
24	25
25	18
26	51
27	33
28	50
29	19
30	48
31	35
32	55
33	20
34	54
35	34
36	52
37	22
38	62
39	40
40	61
41	21
42	60
43	41
44	53
45	28
46	56
47	36
48	63
49	27
50	91
51	64
52	93
53	29
54	59
55	38
56	57
57	31
58	58
59	37
60	100
61	65
62	95
63	30
64	92
65	66
66	101
67	39
68	99
69	68
70	110
71	42

[1, 3, 2, 6, 4, 12, 8, 13, 5, 15, 10, 26, 16, 23, 7, 14, 9, 24, 17, 49, 32, 43, 11, 25, 18, 51, 33, 50, 19, 48, 35, 55, 20, 54, 34, 52, 22, 62, 40, 61, 21, 60, 41, 53, 28, 56, 36, 63, 27, 91, 64, 93, 29, 59, 38, 57, 31, 58, 37, 100, 65, 95, 30, 92, 66, 101, 39, 99, 68, 110, 42]

cp's OEIS Frontend

A116626 a(1)=1; a(odd n) = a(n-1) XOR a(n-2), for a(even n) we find the first i > 1 such that neither i nor (i XOR A116626(n-1)) is present in A116626(1..n-1), in which case a(n) = (i XOR A116626(n-1)).

Table of values

List of values

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	8
8	13
9	5
10	15
11	10
12	26
13	16
14	23
15	7
16	14
17	9
18	24
19	17
20	49
21	32
22	43
23	11
24	25
25	18
26	51
27	33
28	50
29	19
30	48
31	35
32	55
33	20
34	54
35	34
36	52
37	22
38	62
39	40
40	61
41	21
42	60
43	41
44	53
45	28
46	56
47	36
48	63
49	27
50	91
51	64
52	93
53	29
54	59
55	38
56	57
57	31
58	58
59	37
60	100
61	65
62	95
63	30
64	92
65	66
66	101
67	39
68	99
69	68
70	110
71	42

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	8
8	13
9	5
10	15
11	10
12	26
13	16
14	23
15	7
16	14
17	9
18	24
19	17
20	49
21	32
22	43
23	11
24	25
25	18
26	51
27	33
28	50
29	19
30	48
31	35
32	55
33	20
34	54
35	34
36	52
37	22
38	62
39	40
40	61
41	21
42	60
43	41
44	53
45	28
46	56
47	36
48	63
49	27
50	91
51	64
52	93
53	29
54	59
55	38
56	57
57	31
58	58
59	37
60	100
61	65
62	95
63	30
64	92
65	66
66	101
67	39
68	99
69	68
70	110
71	42

n	a(n)
1	1
2	3
3	2
4	6
5	4
6	12
7	8
8	13
9	5
10	15
11	10
12	26
13	16
14	23
15	7
16	14
17	9
18	24
19	17
20	49
21	32
22	43
23	11
24	25
25	18
26	51
27	33
28	50
29	19
30	48
31	35
32	55
33	20
34	54
35	34
36	52
37	22
38	62
39	40
40	61
41	21
42	60
43	41
44	53
45	28
46	56
47	36
48	63
49	27
50	91
51	64
52	93
53	29
54	59
55	38
56	57
57	31
58	58
59	37
60	100
61	65
62	95
63	30
64	92
65	66
66	101
67	39
68	99
69	68
70	110
71	42