A026780 - cp's OEIS frontend

A026780 Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1 <= k <= n-1, T(n,k) = T(n-1,k-1) + T(n-2,k-1) + T(n-1,k) if 1 <= k <= floor(n/2), else T(n,k) = T(n-1,k-1) + T(n-1,k).

n	a(n)
0	1
1	1
2	1
3	1
4	3
5	1
6	1
7	5
8	4
9	1
10	1
11	7
12	12
13	5
14	1
15	1
16	9
17	24
18	17
19	6
20	1
21	1
22	11
23	40
24	53
25	23
26	7
27	1
28	1
29	13
30	60
31	117
32	76
33	30
34	8
35	1
36	1
37	15
38	84
39	217
40	246
41	106
42	38
43	9
44	1
45	1
46	17
47	112
48	361
49	580
50	352
51	144
52	47
53	10
54	1
55	1
56	19
57	144
58	557
59	1158
60	1178
61	496
62	191
63	57
64	11
65	1

[1, 1, 1, 1, 3, 1, 1, 5, 4, 1, 1, 7, 12, 5, 1, 1, 9, 24, 17, 6, 1, 1, 11, 40, 53, 23, 7, 1, 1, 13, 60, 117, 76, 30, 8, 1, 1, 15, 84, 217, 246, 106, 38, 9, 1, 1, 17, 112, 361, 580, 352, 144, 47, 10, 1, 1, 19, 144, 557, 1158, 1178, 496, 191, 57, 11, 1]

cp's OEIS Frontend

A026780 Triangular array T read by rows: T(n,0)=T(n,n)=1 for n >= 0; for n >= 2 and 1 <= k <= n-1, T(n,k) = T(n-1,k-1) + T(n-2,k-1) + T(n-1,k) if 1 <= k <= floor(n/2), else T(n,k) = T(n-1,k-1) + T(n-1,k).

Table of values

List of values