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.

A220933 Equals two maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..2 nX4 array.

Table of values

n a(n)
1 4
2 52
3 673
4 9107
5 123958
6 1686304
7 22931365
8 311813067
9 4239917031
10 57652874111
11 783943412638
12 10659785895199
13 144948006719997
14 1970951840091756
15 26800307525626867
16 364421123267042408
17 4955269821323438717

List of values

[4, 52, 673, 9107, 123958, 1686304, 22931365, 311813067, 4239917031, 57652874111, 783943412638, 10659785895199, 144948006719997, 1970951840091756, 26800307525626867, 364421123267042408, 4955269821323438717]

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

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