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.

A123779 Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 4 which is symmetric after a rotation by 180 degrees.

Table of values

n a(n)
1 1
2 1
3 21
4 67
5 849
6 3185
7 39868
8 162562
9 2027829

List of values

[1, 1, 21, 67, 849, 3185, 39868, 162562, 2027829]