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.

A002690 a(n) = (n+1) * (2*n)! / n!.

Table of values

n a(n)
0 1
1 4
2 36
3 480
4 8400
5 181440
6 4656960
7 138378240
8 4670265600
9 176432256000
10 7374868300800
11 337903056691200
12 16838835658444800
13 906706535454720000
14 52459449551308800000
15 3245491278907637760000
16 213796737998040637440000
17 14940619102451310428160000
18 1103945744792235714969600000

List of values

[1, 4, 36, 480, 8400, 181440, 4656960, 138378240, 4670265600, 176432256000, 7374868300800, 337903056691200, 16838835658444800, 906706535454720000, 52459449551308800000, 3245491278907637760000, 213796737998040637440000, 14940619102451310428160000, 1103945744792235714969600000]

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

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