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.

A200053 Number of -4..4 arrays X (0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing.

Table of values

n a(n)
1 1
2 8
3 36
4 172
5 840
6 4172
7 20978
8 106674
9 545698
10 2811236
11 14534258
12 75522854
13 393338058
14 2056376914
15 10767639532
16 56550307652
17 297322835298
18 1567022163228
19 8265441146830
20 43685281805084
21 231022736833454
22 1223830782531260

List of values

[1, 8, 36, 172, 840, 4172, 20978, 106674, 545698, 2811236, 14534258, 75522854, 393338058, 2056376914, 10767639532, 56550307652, 297322835298, 1567022163228, 8265441146830, 43685281805084, 231022736833454, 1223830782531260]

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

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