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.

A355575 a(n) = n! * Sum_{k=0..floor(n/3)} k^(n - 3*k)/k!.

Table of values

n a(n)
0 1
1 0
2 0
3 6
4 24
5 120
6 1080
7 10080
8 120960
9 1874880
10 34473600
11 738460800
12 17982518400
13 489858969600
14 14834839219200
15 498452777222400
16 18583796335104000
17 768773914900992000
18 35220800475250790400
19 1779227869201400217600
20 98469904378626772992000

List of values

[1, 0, 0, 6, 24, 120, 1080, 10080, 120960, 1874880, 34473600, 738460800, 17982518400, 489858969600, 14834839219200, 498452777222400, 18583796335104000, 768773914900992000, 35220800475250790400, 1779227869201400217600, 98469904378626772992000]