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.

A220331 Equals two maps: number of 4 X n binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 4 X n array.

Table of values

n a(n)
1 1
2 37
3 508
4 6657
5 92093
6 1335202
7 18836493
8 265346645
9 3750121527

List of values

[1, 37, 508, 6657, 92093, 1335202, 18836493, 265346645, 3750121527]