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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.

A331638 Number of binary matrices with nonzero rows, a total of n ones and each column with the same number of ones and columns in nonincreasing lexicographic order.

Table of values

n a(n)
1 1
2 3
3 5
4 16
5 17
6 140
7 65
8 1395
9 2969
10 22176
11 1025
12 1050766
13 4097
14 13010328
15 128268897
16 637598438
17 65537
18 64864962683
19 262145
20 1676258452736
21 28683380484257
22 24908619669860
23 4194305
24 30567710172480050
25 8756434134071649
26 62128557507554504
27 21271147396968151093

List of values

[1, 3, 5, 16, 17, 140, 65, 1395, 2969, 22176, 1025, 1050766, 4097, 13010328, 128268897, 637598438, 65537, 64864962683, 262145, 1676258452736, 28683380484257, 24908619669860, 4194305, 30567710172480050, 8756434134071649, 62128557507554504, 21271147396968151093]

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

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