A131225 - cp's OEIS frontend

A131225 Triangle read by rows: T(n,k) = 2*k - (1 + (-1)^(n-k))/2 (1 <= k <= n).

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

[1, 2, 3, 1, 4, 5, 2, 3, 6, 7, 1, 4, 5, 8, 9, 2, 3, 6, 7, 10, 11, 1, 4, 5, 8, 9, 12, 13, 2, 3, 6, 7, 10, 11, 14, 15, 1, 4, 5, 8, 9, 12, 13, 16, 17, 2, 3, 6, 7, 10, 11, 14, 15, 18, 19, 1, 4, 5, 8, 9, 12, 13, 16, 17, 20, 21, 2, 3, 6, 7, 10, 11, 14, 15, 18, 19, 22, 23]

cp's OEIS Frontend

A131225 Triangle read by rows: T(n,k) = 2*k - (1 + (-1)^(n-k))/2 (1 <= k <= n).

Table of values

List of values

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

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

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