A122155 - cp's OEIS frontend

A122155 Simple involution of natural numbers: List each block of (2^k)-1 numbers (from (2^k)+1 to 2^(k+1) - 1) in reverse order and fix the powers of 2.

n	a(n)
0	0
1	1
2	2
3	3
4	4
5	7
6	6
7	5
8	8
9	15
10	14
11	13
12	12
13	11
14	10
15	9
16	16
17	31
18	30
19	29
20	28
21	27
22	26
23	25
24	24
25	23
26	22
27	21
28	20
29	19
30	18
31	17
32	32
33	63
34	62
35	61
36	60
37	59
38	58
39	57
40	56
41	55
42	54
43	53
44	52
45	51
46	50
47	49
48	48
49	47
50	46
51	45
52	44
53	43
54	42
55	41
56	40
57	39
58	38
59	37
60	36
61	35
62	34
63	33
64	64
65	127
66	126
67	125
68	124
69	123

[0, 1, 2, 3, 4, 7, 6, 5, 8, 15, 14, 13, 12, 11, 10, 9, 16, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 32, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 64, 127, 126, 125, 124, 123]

cp's OEIS Frontend

A122155 Simple involution of natural numbers: List each block of (2^k)-1 numbers (from (2^k)+1 to 2^(k+1) - 1) in reverse order and fix the powers of 2.

Table of values

List of values

n	a(n)
0	0
1	1
2	2
3	3
4	4
5	7
6	6
7	5
8	8
9	15
10	14
11	13
12	12
13	11
14	10
15	9
16	16
17	31
18	30
19	29
20	28
21	27
22	26
23	25
24	24
25	23
26	22
27	21
28	20
29	19
30	18
31	17
32	32
33	63
34	62
35	61
36	60
37	59
38	58
39	57
40	56
41	55
42	54
43	53
44	52
45	51
46	50
47	49
48	48
49	47
50	46
51	45
52	44
53	43
54	42
55	41
56	40
57	39
58	38
59	37
60	36
61	35
62	34
63	33
64	64
65	127
66	126
67	125
68	124
69	123

n	a(n)
0	0
1	1
2	2
3	3
4	4
5	7
6	6
7	5
8	8
9	15
10	14
11	13
12	12
13	11
14	10
15	9
16	16
17	31
18	30
19	29
20	28
21	27
22	26
23	25
24	24
25	23
26	22
27	21
28	20
29	19
30	18
31	17
32	32
33	63
34	62
35	61
36	60
37	59
38	58
39	57
40	56
41	55
42	54
43	53
44	52
45	51
46	50
47	49
48	48
49	47
50	46
51	45
52	44
53	43
54	42
55	41
56	40
57	39
58	38
59	37
60	36
61	35
62	34
63	33
64	64
65	127
66	126
67	125
68	124
69	123

n	a(n)
0	0
1	1
2	2
3	3
4	4
5	7
6	6
7	5
8	8
9	15
10	14
11	13
12	12
13	11
14	10
15	9
16	16
17	31
18	30
19	29
20	28
21	27
22	26
23	25
24	24
25	23
26	22
27	21
28	20
29	19
30	18
31	17
32	32
33	63
34	62
35	61
36	60
37	59
38	58
39	57
40	56
41	55
42	54
43	53
44	52
45	51
46	50
47	49
48	48
49	47
50	46
51	45
52	44
53	43
54	42
55	41
56	40
57	39
58	38
59	37
60	36
61	35
62	34
63	33
64	64
65	127
66	126
67	125
68	124
69	123