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.

A123822 Number of ways to build a contiguous building with n LEGO blocks of size 2 X 2 on top of a fixed block of the same size so that the building is symmetric after a rotation by 180 degrees.

Table of values

n a(n)
1 1
2 5
3 9
4 44
5 111
6 576
7 1541
8 8199
9 23750
10 127654
11 384817
12 2083235

List of values

[1, 5, 9, 44, 111, 576, 1541, 8199, 23750, 127654, 384817, 2083235]

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

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