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.

A151648 Number of permutations of 5 indistinguishable copies of 1..n with exactly 3 adjacent element pairs in decreasing order.

Table of values

n a(n)
1 0
2 100
3 52800
4 6021225
5 447069750
6 28203920250
7 1662432014600
8 95167951614675
9 5379642996402350
10 302454892260579500
11 16965492408059468000
12 950717312310731109725
13 53255101624187593866550
14 2982626301173304400020350
15 167034793385579317725373000
16 9354122482050520106734846375

List of values

[0, 100, 52800, 6021225, 447069750, 28203920250, 1662432014600, 95167951614675, 5379642996402350, 302454892260579500, 16965492408059468000, 950717312310731109725, 53255101624187593866550, 2982626301173304400020350, 167034793385579317725373000, 9354122482050520106734846375]

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

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