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.

A177605 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, up, up, up.

Table of values

n a(n)
0 1
1 1
2 20
3 1680
4 369600
5 166923119
6 134612399509
7 176468898415460
8 351456009607660440
9 1010384984894493146400
10 4028532188816344883922611
11 21572165225621811583520157531
12 151100918612288209338643024889160
13 1354217120536797195675961944817053840

List of values

[1, 1, 20, 1680, 369600, 166923119, 134612399509, 176468898415460, 351456009607660440, 1010384984894493146400, 4028532188816344883922611, 21572165225621811583520157531, 151100918612288209338643024889160, 1354217120536797195675961944817053840]

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

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