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.

A217803 Number of alternating permutations on 2n+1 letters that avoid a certain pattern of length 4 (see Lewis, 2012, Appendix, for precise definition).

Table of values

n a(n)
0 1
1 2
2 12
3 108
4 1202
5 15234
6 210696
7 3102296
8 47875884

List of values

[1, 2, 12, 108, 1202, 15234, 210696, 3102296, 47875884]