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.

A197458 Number of n X n binary matrices with at most two 1's in each row and column, other entries 0.

Table of values

n a(n)
0 1
1 2
2 16
3 265
4 7343
5 304186
6 17525812
7 1336221251
8 129980132305
9 15686404067098
10 2297230134084416
11 400977650310256537
12 82188611938415464231
13 19536244019455339261970
14 5328019975275896220786388
15 1651867356348327784988233291
16 577522171260292028520919811777

List of values

[1, 2, 16, 265, 7343, 304186, 17525812, 1336221251, 129980132305, 15686404067098, 2297230134084416, 400977650310256537, 82188611938415464231, 19536244019455339261970, 5328019975275896220786388, 1651867356348327784988233291, 577522171260292028520919811777]

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

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