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.

A243870 Number of Dyck paths of semilength n avoiding the consecutive steps UDUUUDDDUD (with U=(1,1), D=(1,-1)).

Table of values

n a(n)
0 1
1 1
2 2
3 5
4 14
5 41
6 129
7 419
8 1395
9 4737
10 16338
11 57086
12 201642
13 718855
14 2583149
15 9346594
16 34023934
17 124519805
18 457889432
19 1690971387
20 6268769864
21 23320702586
22 87031840257
23 325741788736
24 1222429311437
25 4598725914380
26 17339388194985
27 65514945338284

List of values

[1, 1, 2, 5, 14, 41, 129, 419, 1395, 4737, 16338, 57086, 201642, 718855, 2583149, 9346594, 34023934, 124519805, 457889432, 1690971387, 6268769864, 23320702586, 87031840257, 325741788736, 1222429311437, 4598725914380, 17339388194985, 65514945338284]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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