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.

A258397 Number of 2n-length strings of balanced parentheses of exactly 9 different types that are introduced in ascending order.

Table of values

n a(n)
9 4862
10 755820
11 67897830
12 4633467300
13 267074035800
14 13733597077200
15 650800305634050
16 29021018652697500
17 1235362166419751370
18 50713478000403718500
19 2022835296688063807950
20 78843505678630977784500
21 3016017325414346802772080
22 113617986954086473298668800

List of values

[4862, 755820, 67897830, 4633467300, 267074035800, 13733597077200, 650800305634050, 29021018652697500, 1235362166419751370, 50713478000403718500, 2022835296688063807950, 78843505678630977784500, 3016017325414346802772080, 113617986954086473298668800]

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

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