A026584 - cp's OEIS frontend

A026584 Irregular triangular array T read by rows: T(i,0) = T(i,2i) = 1 for i >= 0; T(i,1) = T(i,2i-1) = floor(i/2) for i >= 1; and for i >= 2 and j = 2..2i-2, T(i,j) = T(i-1,j-2) + T(i-1,j-1) + T(i-1,j) if i+j is odd, and T(i,j) = T(i-1,j-2) + T(i-1,j) if i+j is even.

n	a(n)
1	1
2	1
3	0
4	1
5	1
6	1
7	2
8	1
9	1
10	1
11	1
12	4
13	2
14	4
15	1
16	1
17	1
18	2
19	5
20	7
21	8
22	7
23	5
24	2
25	1
26	1
27	2
28	8
29	9
30	20
31	14
32	20
33	9
34	8
35	2
36	1
37	1
38	3
39	9
40	19
41	28
42	43
43	40
44	43
45	28
46	19
47	9
48	3
49	1
50	1
51	3
52	13
53	22
54	56
55	62
56	111
57	86
58	111
59	62
60	56
61	22
62	13
63	3
64	1
65	1
66	4
67	14
68	38
69	69
70	140
71	167
72	259
73	222
74	259
75	167
76	140
77	69
78	38
79	14
80	4
81	1

[1, 1, 0, 1, 1, 1, 2, 1, 1, 1, 1, 4, 2, 4, 1, 1, 1, 2, 5, 7, 8, 7, 5, 2, 1, 1, 2, 8, 9, 20, 14, 20, 9, 8, 2, 1, 1, 3, 9, 19, 28, 43, 40, 43, 28, 19, 9, 3, 1, 1, 3, 13, 22, 56, 62, 111, 86, 111, 62, 56, 22, 13, 3, 1, 1, 4, 14, 38, 69, 140, 167, 259, 222, 259, 167, 140, 69, 38, 14, 4, 1]

cp's OEIS Frontend

A026584 Irregular triangular array T read by rows: T(i,0) = T(i,2i) = 1 for i >= 0; T(i,1) = T(i,2i-1) = floor(i/2) for i >= 1; and for i >= 2 and j = 2..2i-2, T(i,j) = T(i-1,j-2) + T(i-1,j-1) + T(i-1,j) if i+j is odd, and T(i,j) = T(i-1,j-2) + T(i-1,j) if i+j is even.

Table of values

List of values

n	a(n)
1	1
2	1
3	0
4	1
5	1
6	1
7	2
8	1
9	1
10	1
11	1
12	4
13	2
14	4
15	1
16	1
17	1
18	2
19	5
20	7
21	8
22	7
23	5
24	2
25	1
26	1
27	2
28	8
29	9
30	20
31	14
32	20
33	9
34	8
35	2
36	1
37	1
38	3
39	9
40	19
41	28
42	43
43	40
44	43
45	28
46	19
47	9
48	3
49	1
50	1
51	3
52	13
53	22
54	56
55	62
56	111
57	86
58	111
59	62
60	56
61	22
62	13
63	3
64	1
65	1
66	4
67	14
68	38
69	69
70	140
71	167
72	259
73	222
74	259
75	167
76	140
77	69
78	38
79	14
80	4
81	1

n	a(n)
1	1
2	1
3	0
4	1
5	1
6	1
7	2
8	1
9	1
10	1
11	1
12	4
13	2
14	4
15	1
16	1
17	1
18	2
19	5
20	7
21	8
22	7
23	5
24	2
25	1
26	1
27	2
28	8
29	9
30	20
31	14
32	20
33	9
34	8
35	2
36	1
37	1
38	3
39	9
40	19
41	28
42	43
43	40
44	43
45	28
46	19
47	9
48	3
49	1
50	1
51	3
52	13
53	22
54	56
55	62
56	111
57	86
58	111
59	62
60	56
61	22
62	13
63	3
64	1
65	1
66	4
67	14
68	38
69	69
70	140
71	167
72	259
73	222
74	259
75	167
76	140
77	69
78	38
79	14
80	4
81	1

n	a(n)
1	1
2	1
3	0
4	1
5	1
6	1
7	2
8	1
9	1
10	1
11	1
12	4
13	2
14	4
15	1
16	1
17	1
18	2
19	5
20	7
21	8
22	7
23	5
24	2
25	1
26	1
27	2
28	8
29	9
30	20
31	14
32	20
33	9
34	8
35	2
36	1
37	1
38	3
39	9
40	19
41	28
42	43
43	40
44	43
45	28
46	19
47	9
48	3
49	1
50	1
51	3
52	13
53	22
54	56
55	62
56	111
57	86
58	111
59	62
60	56
61	22
62	13
63	3
64	1
65	1
66	4
67	14
68	38
69	69
70	140
71	167
72	259
73	222
74	259
75	167
76	140
77	69
78	38
79	14
80	4
81	1