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.

A177596 Number of permutations of 3 copies of 1..n avoiding adjacent step pattern up, up.

Table of values

n a(n)
0 1
1 1
2 20
3 1109
4 149777
5 40505320
6 19324787629
7 14885613436177
8 17346023517866756
9 29095672934852234945
10 67554301929824585326841
11 210353969049597164741983000
12 855886755812900060235077981449
13 4452236180954942685194928540509281

List of values

[1, 1, 20, 1109, 149777, 40505320, 19324787629, 14885613436177, 17346023517866756, 29095672934852234945, 67554301929824585326841, 210353969049597164741983000, 855886755812900060235077981449, 4452236180954942685194928540509281]

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

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