A115991 - cp's OEIS frontend

A115991 Number triangle T(n,k) = Sum_{j=0..n} C(n-k,j-k)C(j,n-j)2^(n-j).

n	a(n)
0	1
1	1
2	1
3	5
4	3
5	1
6	13
7	9
8	5
9	1
10	49
11	31
12	17
13	7
14	1
15	161
16	105
17	61
18	29
19	9
20	1
21	581
22	371
23	217
24	111
25	45
26	11
27	1
28	2045
29	1313
30	781
31	417
32	189
33	65
34	13
35	1
36	7393
37	4719
38	2825
39	1551
40	753
41	303
42	89
43	15
44	1
45	26689
46	17041
47	10277
48	5757
49	2921
50	1289
51	461
52	117
53	17
54	1

[1, 1, 1, 5, 3, 1, 13, 9, 5, 1, 49, 31, 17, 7, 1, 161, 105, 61, 29, 9, 1, 581, 371, 217, 111, 45, 11, 1, 2045, 1313, 781, 417, 189, 65, 13, 1, 7393, 4719, 2825, 1551, 753, 303, 89, 15, 1, 26689, 17041, 10277, 5757, 2921, 1289, 461, 117, 17, 1]

cp's OEIS Frontend

A115991 Number triangle T(n,k) = Sum_{j=0..n} C(n-k,j-k)C(j,n-j)2^(n-j).

Table of values

List of values

cp's OEIS Frontend

A115991 Number triangle T(n,k) = Sum_{j=0..n} C(n-k,j-k)*C(j,n-j)*2^(n-j).

Table of values

List of values

A115991 Number triangle T(n,k) = Sum_{j=0..n} C(n-k,j-k)C(j,n-j)2^(n-j).