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.

A287845 Number of Dyck paths of semilength n such that each positive level up to the highest nonempty level has exactly two peaks.

Table of values

n a(n)
0 1
1 0
2 1
3 0
4 0
5 3
6 6
7 0
8 9
9 54
10 138
11 207
12 360
13 1368
14 4545
15 11304
16 25182
17 61605
18 173916
19 498798
20 1347417
21 3497328
22 9147060
23 24630669
24 67414590
25 184065966
26 498495303
27 1345622436
28 3642036804
29 9900361107
30 26982011250
31 73570082760
32 200540053395
33 546660151722

List of values

[1, 0, 1, 0, 0, 3, 6, 0, 9, 54, 138, 207, 360, 1368, 4545, 11304, 25182, 61605, 173916, 498798, 1347417, 3497328, 9147060, 24630669, 67414590, 184065966, 498495303, 1345622436, 3642036804, 9900361107, 26982011250, 73570082760, 200540053395, 546660151722]

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

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