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.

A220325 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..1 nX4 array.

Table of values

n a(n)
1 4
2 48
3 572
4 6657
5 76627
6 876714
7 10004541
8 114058230
9 1299991681
10 14816159113
11 168863397427
12 1924606619479
13 21935746576784
14 250014218249170
15 2849559239020408
16 32478119824983512
17 370172462886188547

List of values

[4, 48, 572, 6657, 76627, 876714, 10004541, 114058230, 1299991681, 14816159113, 168863397427, 1924606619479, 21935746576784, 250014218249170, 2849559239020408, 32478119824983512, 370172462886188547]

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

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