A287776 - cp's OEIS frontend

A287776 Number of Dyck paths of semilength n such that every peak at level y > 1 is preceded by (at least) one peak at level y-1 and is followed by (at least) one peak at level y-1.

n	a(n)
0	1
1	1
2	1
3	1
4	2
5	4
6	8
7	17
8	39
9	95
10	241
11	629
12	1679
13	4572
14	12684
15	35812
16	102774
17	299371
18	883848
19	2641121
20	7978262
21	24337821
22	74908008
23	232451921
24	726831776
25	2288799963
26	7255401745
27	23143158678
28	74256591422
29	239582207959
30	777047305709
31	2532730030266
32	8293970682858

[1, 1, 1, 1, 2, 4, 8, 17, 39, 95, 241, 629, 1679, 4572, 12684, 35812, 102774, 299371, 883848, 2641121, 7978262, 24337821, 74908008, 232451921, 726831776, 2288799963, 7255401745, 23143158678, 74256591422, 239582207959, 777047305709, 2532730030266, 8293970682858]

cp's OEIS Frontend

A287776 Number of Dyck paths of semilength n such that every peak at level y > 1 is preceded by (at least) one peak at level y-1 and is followed by (at least) one peak at level y-1.

Table of values

List of values