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.

A245854 Number of preferential arrangements of n labeled elements such that the minimal number of elements per rank equals 1.

Table of values

n a(n)
1 1
2 2
3 12
4 68
5 520
6 4542
7 46550
8 540136
9 7045020
10 101865410
11 1619046418
12 28053492348
13 526430246264
14 10636085523910
15 230214619661790
16 5314695463338704
17 130356558777712468
18 3385311352838750538
19 92797887464933030762
20 2677623216872061223780
21 81123642038690958720048

List of values

[1, 2, 12, 68, 520, 4542, 46550, 540136, 7045020, 101865410, 1619046418, 28053492348, 526430246264, 10636085523910, 230214619661790, 5314695463338704, 130356558777712468, 3385311352838750538, 92797887464933030762, 2677623216872061223780, 81123642038690958720048]

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

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