A249494 - cp's OEIS frontend

A249494 Lexicographically earliest permutation of the positive integers such that the parity of the first digit of a(n+1) equals that of a(n)'s last digit.

n	a(n)
1	1
2	3
3	5
4	7
5	9
6	10
7	2
8	4
9	6
10	8
11	20
12	21
13	11
14	12
15	22
16	23
17	13
18	14
19	24
20	25
21	15
22	16
23	26
24	27
25	17
26	18
27	28
28	29
29	19
30	30
31	40
32	41
33	31
34	32
35	42
36	43
37	33
38	34
39	44
40	45
41	35
42	36
43	46
44	47
45	37
46	38
47	48
48	49
49	39
50	50
51	60
52	61
53	51
54	52
55	62
56	63
57	53
58	54
59	64
60	65
61	55
62	56
63	66
64	67
65	57
66	58
67	68
68	69
69	59
70	70
71	80
72	81
73	71
74	72
75	82
76	83
77	73
78	74
79	84
80	85
81	75
82	76
83	86
84	87
85	77
86	78
87	88
88	89
89	79
90	90
91	200

[1, 3, 5, 7, 9, 10, 2, 4, 6, 8, 20, 21, 11, 12, 22, 23, 13, 14, 24, 25, 15, 16, 26, 27, 17, 18, 28, 29, 19, 30, 40, 41, 31, 32, 42, 43, 33, 34, 44, 45, 35, 36, 46, 47, 37, 38, 48, 49, 39, 50, 60, 61, 51, 52, 62, 63, 53, 54, 64, 65, 55, 56, 66, 67, 57, 58, 68, 69, 59, 70, 80, 81, 71, 72, 82, 83, 73, 74, 84, 85, 75, 76, 86, 87, 77, 78, 88, 89, 79, 90, 200]

cp's OEIS Frontend

A249494 Lexicographically earliest permutation of the positive integers such that the parity of the first digit of a(n+1) equals that of a(n)'s last digit.

Table of values

List of values

n	a(n)
1	1
2	3
3	5
4	7
5	9
6	10
7	2
8	4
9	6
10	8
11	20
12	21
13	11
14	12
15	22
16	23
17	13
18	14
19	24
20	25
21	15
22	16
23	26
24	27
25	17
26	18
27	28
28	29
29	19
30	30
31	40
32	41
33	31
34	32
35	42
36	43
37	33
38	34
39	44
40	45
41	35
42	36
43	46
44	47
45	37
46	38
47	48
48	49
49	39
50	50
51	60
52	61
53	51
54	52
55	62
56	63
57	53
58	54
59	64
60	65
61	55
62	56
63	66
64	67
65	57
66	58
67	68
68	69
69	59
70	70
71	80
72	81
73	71
74	72
75	82
76	83
77	73
78	74
79	84
80	85
81	75
82	76
83	86
84	87
85	77
86	78
87	88
88	89
89	79
90	90
91	200

n	a(n)
1	1
2	3
3	5
4	7
5	9
6	10
7	2
8	4
9	6
10	8
11	20
12	21
13	11
14	12
15	22
16	23
17	13
18	14
19	24
20	25
21	15
22	16
23	26
24	27
25	17
26	18
27	28
28	29
29	19
30	30
31	40
32	41
33	31
34	32
35	42
36	43
37	33
38	34
39	44
40	45
41	35
42	36
43	46
44	47
45	37
46	38
47	48
48	49
49	39
50	50
51	60
52	61
53	51
54	52
55	62
56	63
57	53
58	54
59	64
60	65
61	55
62	56
63	66
64	67
65	57
66	58
67	68
68	69
69	59
70	70
71	80
72	81
73	71
74	72
75	82
76	83
77	73
78	74
79	84
80	85
81	75
82	76
83	86
84	87
85	77
86	78
87	88
88	89
89	79
90	90
91	200

n	a(n)
1	1
2	3
3	5
4	7
5	9
6	10
7	2
8	4
9	6
10	8
11	20
12	21
13	11
14	12
15	22
16	23
17	13
18	14
19	24
20	25
21	15
22	16
23	26
24	27
25	17
26	18
27	28
28	29
29	19
30	30
31	40
32	41
33	31
34	32
35	42
36	43
37	33
38	34
39	44
40	45
41	35
42	36
43	46
44	47
45	37
46	38
47	48
48	49
49	39
50	50
51	60
52	61
53	51
54	52
55	62
56	63
57	53
58	54
59	64
60	65
61	55
62	56
63	66
64	67
65	57
66	58
67	68
68	69
69	59
70	70
71	80
72	81
73	71
74	72
75	82
76	83
77	73
78	74
79	84
80	85
81	75
82	76
83	86
84	87
85	77
86	78
87	88
88	89
89	79
90	90
91	200