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.

A366924 Number of 2n-step walks on square lattice starting and ending at the origin with first step north and avoiding early returns.

Table of values

n a(n)
1 1
2 5
3 44
4 469
5 5516
6 68892
7 896016
8 11998869
9 164259308
10 2287663804
11 32303714576
12 461352451292
13 6651528522256
14 96669999247184
15 1414652852290752
16 20825721430968213
17 308191001159544876
18 4581880220433822108
19 68398967956430765712
20 1024826569020715088508
21 15405900278361291658896

List of values

[1, 5, 44, 469, 5516, 68892, 896016, 11998869, 164259308, 2287663804, 32303714576, 461352451292, 6651528522256, 96669999247184, 1414652852290752, 20825721430968213, 308191001159544876, 4581880220433822108, 68398967956430765712, 1024826569020715088508, 15405900278361291658896]

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

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