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.

A343580 a(n) = abs(A021009(n, floor(n/2))).

Table of values

n a(n)
0 1
1 1
2 4
3 18
4 72
5 600
6 2400
7 29400
8 117600
9 1905120
10 7620480
11 153679680
12 614718720
13 14841066240
14 59364264960
15 1669619952000
16 6678479808000
17 214453407168000
18 857813628672000
19 30967071995059200
20 123868287980236800
21 4965992272662220800
22 19863969090648883200

List of values

[1, 1, 4, 18, 72, 600, 2400, 29400, 117600, 1905120, 7620480, 153679680, 614718720, 14841066240, 59364264960, 1669619952000, 6678479808000, 214453407168000, 857813628672000, 30967071995059200, 123868287980236800, 4965992272662220800, 19863969090648883200]

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

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