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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.

A180056 The number of permutations of {1,2,...,2n} with n ascents.

Table of values

n a(n)
0 1
1 1
2 11
3 302
4 15619
5 1310354
6 162512286
7 27971176092
8 6382798925475
9 1865385657780650
10 679562217794156938
11 301958232385734088196
12 160755658074834738495566
13 101019988341178648636047412
14 73990373947612503295166622044
15 62481596875767023932367207962680

List of values

[1, 1, 11, 302, 15619, 1310354, 162512286, 27971176092, 6382798925475, 1865385657780650, 679562217794156938, 301958232385734088196, 160755658074834738495566, 101019988341178648636047412, 73990373947612503295166622044, 62481596875767023932367207962680]

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

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