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.

A151634 Number of permutations of 3 indistinguishable copies of 1..n with exactly 4 adjacent element pairs in decreasing order.

Table of values

n a(n)
1 0
2 0
3 405
4 128124
5 12750255
6 789300477
7 38464072830
8 1641724670475
9 64856779908606
10 2445752640197970
11 89642032274378115
12 3228334377697738350
13 115003717118946936945
14 4069184219056622926539
15 143377786266629066071740
16 5038841894823365860640997
17 176801555321207696717476200

List of values

[0, 0, 405, 128124, 12750255, 789300477, 38464072830, 1641724670475, 64856779908606, 2445752640197970, 89642032274378115, 3228334377697738350, 115003717118946936945, 4069184219056622926539, 143377786266629066071740, 5038841894823365860640997, 176801555321207696717476200]

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

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