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.

A331648 Number of nonnegative integer matrices with distinct nonzero rows, total sum n and columns with equal sums.

Table of values

n a(n)
1 1
2 4
3 16
4 91
5 546
6 5094
7 47306
8 561190
9 7098943
10 103345704
11 1622632638
12 28216141886
13 526858348514
14 10659286804538
15 230286817182060
16 5319206290975993
17 130370767029136518
18 3386434807625742926
19 92801587319328412310
20 2677967917777310591454
21 81124837170900250181072

List of values

[1, 4, 16, 91, 546, 5094, 47306, 561190, 7098943, 103345704, 1622632638, 28216141886, 526858348514, 10659286804538, 230286817182060, 5319206290975993, 130370767029136518, 3386434807625742926, 92801587319328412310, 2677967917777310591454, 81124837170900250181072]

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

Content is available under The OEIS End-User License Agreement.