A105640 - cp's OEIS frontend

A105640 Triangle read by rows: T(n,k) is the number of hill-free Dyck paths of semilength n and having k UUDD's, where U=(1,1) and D=(1,-1) (0<=k<=floor(n/2), n>=2). A hill in a Dyck path is a peak at level 1.

n	a(n)
2	0
3	1
4	1
5	1
6	2
7	3
8	1
9	5
10	10
11	3
12	14
13	29
14	13
15	1
16	39
17	89
18	52
19	6
20	111
21	279
22	195
23	36
24	1
25	322
26	881
27	722
28	185
29	10
30	947
31	2806
32	2637
33	867
34	80
35	1
36	2818
37	8997
38	9528
39	3846
40	520
41	15
42	8470
43	28997
44	34163
45	16382
46	2976
47	155
48	1
49	25677
50	93858
51	121749
52	67696
53	15631
54	1246
55	21

[0, 1, 1, 1, 2, 3, 1, 5, 10, 3, 14, 29, 13, 1, 39, 89, 52, 6, 111, 279, 195, 36, 1, 322, 881, 722, 185, 10, 947, 2806, 2637, 867, 80, 1, 2818, 8997, 9528, 3846, 520, 15, 8470, 28997, 34163, 16382, 2976, 155, 1, 25677, 93858, 121749, 67696, 15631, 1246, 21]

cp's OEIS Frontend

A105640 Triangle read by rows: T(n,k) is the number of hill-free Dyck paths of semilength n and having k UUDD's, where U=(1,1) and D=(1,-1) (0<=k<=floor(n/2), n>=2). A hill in a Dyck path is a peak at level 1.

Table of values

List of values