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.

A123833 Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3 which is symmetric after a rotation by 180 degrees.

Table of values

n a(n)
1 1
2 1
3 9
4 22
5 317
6 980
7 13801
8 48756
9 660997
10 2505447

List of values

[1, 1, 9, 22, 317, 980, 13801, 48756, 660997, 2505447]