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.

A151627 Number of permutations of 2 indistinguishable copies of 1..n with exactly 5 adjacent element pairs in decreasing order.

Table of values

n a(n)
1 0
2 0
3 0
4 72
5 27664
6 2864328
7 163809288
8 6727188848
9 225167210712
10 6590156148912
11 175992170793456
12 4407169187423736
13 105396936343707456
14 2437638848729751736
15 55010494951127561400
16 1219075824289276443744
17 26652917330108137129544
18 576864003740129587504224

List of values

[0, 0, 0, 72, 27664, 2864328, 163809288, 6727188848, 225167210712, 6590156148912, 175992170793456, 4407169187423736, 105396936343707456, 2437638848729751736, 55010494951127561400, 1219075824289276443744, 26652917330108137129544, 576864003740129587504224]

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

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