cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A287843 Number of Dyck paths of semilength n such that each level with peaks has exactly two peaks.

Table of values

n a(n)
0 1
1 0
2 1
3 1
4 2
5 5
6 15
7 27
8 76
9 196
10 548
11 1388
12 3621
13 9894
14 27553
15 75346
16 205634
17 563729
18 1565409
19 4370226
20 12191929
21 33980329
22 94874987
23 265668404
24 745652478
25 2095025688
26 5889310438
27 16565399257
28 46633521554
29 131388795335
30 370434641340
31 1044917168292

List of values

[1, 0, 1, 1, 2, 5, 15, 27, 76, 196, 548, 1388, 3621, 9894, 27553, 75346, 205634, 563729, 1565409, 4370226, 12191929, 33980329, 94874987, 265668404, 745652478, 2095025688, 5889310438, 16565399257, 46633521554, 131388795335, 370434641340, 1044917168292]