A146987 - cp's OEIS frontend

A146987 Triangle, read by rows, T(n, k) = binomial(n, k) for n < 2 and binomial(n, k) + 3^(n-1)*binomial(n-2, k -1) otherwise.

n	a(n)
0	1
1	1
2	1
3	1
4	5
5	1
6	1
7	12
8	12
9	1
10	1
11	31
12	60
13	31
14	1
15	1
16	86
17	253
18	253
19	86
20	1
21	1
22	249
23	987
24	1478
25	987
26	249
27	1
28	1
29	736
30	3666
31	7325
32	7325
33	3666
34	736
35	1
36	1
37	2195
38	13150
39	32861
40	43810
41	32861
42	13150
43	2195
44	1
45	1
46	6570
47	45963
48	137865
49	229761
50	229761
51	137865
52	45963
53	6570
54	1

[1, 1, 1, 1, 5, 1, 1, 12, 12, 1, 1, 31, 60, 31, 1, 1, 86, 253, 253, 86, 1, 1, 249, 987, 1478, 987, 249, 1, 1, 736, 3666, 7325, 7325, 3666, 736, 1, 1, 2195, 13150, 32861, 43810, 32861, 13150, 2195, 1, 1, 6570, 45963, 137865, 229761, 229761, 137865, 45963, 6570, 1]

cp's OEIS Frontend

A146987 Triangle, read by rows, T(n, k) = binomial(n, k) for n < 2 and binomial(n, k) + 3^(n-1)*binomial(n-2, k -1) otherwise.

Table of values

List of values