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.

A024199 a(n) = (2n-1)!! * Sum_{k=0..n-1}(-1)^k/(2k+1).

Table of values

n a(n)
0 0
1 1
2 2
3 13
4 76
5 789
6 7734
7 110937
8 1528920
9 28018665
10 497895210
11 11110528485
12 241792844580
13 6361055257725
14 163842638377950
15 4964894559637425
16 147721447995130800
17 5066706567801827025
18 171002070002301095250
19 6548719685561840296125
20 247199273204273879989500

List of values

[0, 1, 2, 13, 76, 789, 7734, 110937, 1528920, 28018665, 497895210, 11110528485, 241792844580, 6361055257725, 163842638377950, 4964894559637425, 147721447995130800, 5066706567801827025, 171002070002301095250, 6548719685561840296125, 247199273204273879989500]

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

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