A054082 - cp's OEIS frontend

A054082 Permutation of N: a(1)=2, a(2)=1 and for each k >= 2, let p(k)=least natural number not already an a(i), q(k)=p(k)+k-1, a(2k-1)=q(k), a(2k)=p(k).

n	a(n)
1	2
2	1
3	4
4	3
5	7
6	5
7	9
8	6
9	12
10	8
11	15
12	10
13	17
14	11
15	20
16	13
17	22
18	14
19	25
20	16
21	28
22	18
23	30
24	19
25	33
26	21
27	36
28	23
29	38
30	24
31	41
32	26
33	43
34	27
35	46
36	29
37	49
38	31
39	51
40	32
41	54
42	34
43	56
44	35
45	59
46	37
47	62
48	39
49	64
50	40
51	67
52	42
53	70
54	44
55	72
56	45
57	75
58	47
59	77
60	48
61	80
62	50
63	83

[2, 1, 4, 3, 7, 5, 9, 6, 12, 8, 15, 10, 17, 11, 20, 13, 22, 14, 25, 16, 28, 18, 30, 19, 33, 21, 36, 23, 38, 24, 41, 26, 43, 27, 46, 29, 49, 31, 51, 32, 54, 34, 56, 35, 59, 37, 62, 39, 64, 40, 67, 42, 70, 44, 72, 45, 75, 47, 77, 48, 80, 50, 83]

cp's OEIS Frontend

A054082 Permutation of N: a(1)=2, a(2)=1 and for each k >= 2, let p(k)=least natural number not already an a(i), q(k)=p(k)+k-1, a(2k-1)=q(k), a(2k)=p(k).

Table of values

List of values

n	a(n)
1	2
2	1
3	4
4	3
5	7
6	5
7	9
8	6
9	12
10	8
11	15
12	10
13	17
14	11
15	20
16	13
17	22
18	14
19	25
20	16
21	28
22	18
23	30
24	19
25	33
26	21
27	36
28	23
29	38
30	24
31	41
32	26
33	43
34	27
35	46
36	29
37	49
38	31
39	51
40	32
41	54
42	34
43	56
44	35
45	59
46	37
47	62
48	39
49	64
50	40
51	67
52	42
53	70
54	44
55	72
56	45
57	75
58	47
59	77
60	48
61	80
62	50
63	83

n	a(n)
1	2
2	1
3	4
4	3
5	7
6	5
7	9
8	6
9	12
10	8
11	15
12	10
13	17
14	11
15	20
16	13
17	22
18	14
19	25
20	16
21	28
22	18
23	30
24	19
25	33
26	21
27	36
28	23
29	38
30	24
31	41
32	26
33	43
34	27
35	46
36	29
37	49
38	31
39	51
40	32
41	54
42	34
43	56
44	35
45	59
46	37
47	62
48	39
49	64
50	40
51	67
52	42
53	70
54	44
55	72
56	45
57	75
58	47
59	77
60	48
61	80
62	50
63	83

n	a(n)
1	2
2	1
3	4
4	3
5	7
6	5
7	9
8	6
9	12
10	8
11	15
12	10
13	17
14	11
15	20
16	13
17	22
18	14
19	25
20	16
21	28
22	18
23	30
24	19
25	33
26	21
27	36
28	23
29	38
30	24
31	41
32	26
33	43
34	27
35	46
36	29
37	49
38	31
39	51
40	32
41	54
42	34
43	56
44	35
45	59
46	37
47	62
48	39
49	64
50	40
51	67
52	42
53	70
54	44
55	72
56	45
57	75
58	47
59	77
60	48
61	80
62	50
63	83