A253180 - cp's OEIS frontend

A253180 Number T(n,k) of 2n-length strings of balanced parentheses of exactly k different types that are introduced in ascending order; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

n	a(n)
0	1
1	0
2	1
3	0
4	2
5	2
6	0
7	5
8	15
9	5
10	0
11	14
12	98
13	84
14	14
15	0
16	42
17	630
18	1050
19	420
20	42
21	0
22	132
23	4092
24	11880
25	8580
26	1980
27	132
28	0
29	429
30	27027
31	129129
32	150150
33	60060
34	9009
35	429
36	0
37	1430
38	181610
39	1381380
40	2432430
41	1501500
42	380380
43	40040
44	1430
45	0
46	4862
47	1239810
48	14707550
49	37777740
50	33795762
51	12864852
52	2246244
53	175032
54	4862

[1, 0, 1, 0, 2, 2, 0, 5, 15, 5, 0, 14, 98, 84, 14, 0, 42, 630, 1050, 420, 42, 0, 132, 4092, 11880, 8580, 1980, 132, 0, 429, 27027, 129129, 150150, 60060, 9009, 429, 0, 1430, 181610, 1381380, 2432430, 1501500, 380380, 40040, 1430, 0, 4862, 1239810, 14707550, 37777740, 33795762, 12864852, 2246244, 175032, 4862]

cp's OEIS Frontend

A253180 Number T(n,k) of 2n-length strings of balanced parentheses of exactly k different types that are introduced in ascending order; triangle T(n,k), n>=0, 0<=k<=n, read by rows.

Table of values

List of values