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.

A169638 Number of multiset permutations of the n initial elements of A005229 with additional element A005229(0)=1.

Table of values

n a(n)
0 1
1 1
2 1
3 4
4 20
5 60
6 420
7 3360
8 30240
9 151200
10 1663200
11 9979200
12 129729600
13 1816214400
14 27243216000
15 217945728000
16 3705077376000
17 66691392768000
18 633568231296000
19 12671364625920000
20 266098657144320000
21 5854170457175040000
22 134645920515025920000
23 1615751046180311040000

List of values

[1, 1, 1, 4, 20, 60, 420, 3360, 30240, 151200, 1663200, 9979200, 129729600, 1816214400, 27243216000, 217945728000, 3705077376000, 66691392768000, 633568231296000, 12671364625920000, 266098657144320000, 5854170457175040000, 134645920515025920000, 1615751046180311040000]

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

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