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.

A215290 Number of permutations of 0..floor((n*6-1)/2) on even squares of an nX6 array such that each row and column of even squares is increasing.

Table of values

n a(n)
1 1
2 20
3 420
4 23100
5 1051050
6 85765680
7 5703417720
8 577185873264
9 48236247979920
10 5595404765670720
11 545152292883918720
12 69506917342699636800
13 7562187114225380722800
14 1033498905610802032116000

List of values

[1, 20, 420, 23100, 1051050, 85765680, 5703417720, 577185873264, 48236247979920, 5595404765670720, 545152292883918720, 69506917342699636800, 7562187114225380722800, 1033498905610802032116000]

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

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