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.

A245856 Number of preferential arrangements of n labeled elements such that the minimal number of elements per rank equals 3.

Table of values

n a(n)
3 1
4 0
5 0
6 20
7 70
8 112
9 1848
10 12840
11 62700
12 591800
13 5484908
14 40589276
15 421291780
16 4704380800
17 46345716880
18 533446290384
19 6931113219780
20 85313661653400
21 1121432682942740
22 16310909250477380
23 237534778732260548
24 3578871132644512672
25 57980168196079811800

List of values

[1, 0, 0, 20, 70, 112, 1848, 12840, 62700, 591800, 5484908, 40589276, 421291780, 4704380800, 46345716880, 533446290384, 6931113219780, 85313661653400, 1121432682942740, 16310909250477380, 237534778732260548, 3578871132644512672, 57980168196079811800]

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

Content is available under The OEIS End-User License Agreement.