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.

A152172 a(n) is the number of Dyck paths of semilength n without height of peaks 0 (mod 3) and height of valleys 1 (mod 3).

Table of values

n a(n)
0 1
1 1
2 2
3 3
4 6
5 12
6 26
7 59
8 138
9 332
10 814
11 2028
12 5118
13 13054
14 33598
15 87143
16 227542
17 597640
18 1577866
19 4185108
20 11146570
21 29798682
22 79932298
23 215072896
24 580327122
25 1569942098
26 4257254850
27 11569980794
28 31508150890
29 85968266198
30 234975421554
31 643317390627

List of values

[1, 1, 2, 3, 6, 12, 26, 59, 138, 332, 814, 2028, 5118, 13054, 33598, 87143, 227542, 597640, 1577866, 4185108, 11146570, 29798682, 79932298, 215072896, 580327122, 1569942098, 4257254850, 11569980794, 31508150890, 85968266198, 234975421554, 643317390627]