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.

A331649 Number of binary matrices with n distinct columns and any number of distinct nonzero rows with 2 ones in every column and columns in decreasing lexicographic order.

Table of values

n a(n)
0 1
1 0
2 3
3 17
4 230
5 3264
6 60338
7 1287062
8 31900620
9 893284155
10 27972470286
11 967596779631
12 36654913572018
13 1509052435744560
14 67089897326522970
15 3203343744126663616
16 163486870943294124046
17 8881542959996746368420
18 511713241494851800728865
19 31165957861936237845310435

List of values

[1, 0, 3, 17, 230, 3264, 60338, 1287062, 31900620, 893284155, 27972470286, 967596779631, 36654913572018, 1509052435744560, 67089897326522970, 3203343744126663616, 163486870943294124046, 8881542959996746368420, 511713241494851800728865, 31165957861936237845310435]

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

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