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.

A331644 Number of nonnegative integer matrices with n columns and any number of distinct nonzero rows with column sums 2.

Table of values

n a(n)
0 1
1 1
2 13
3 313
4 14797
5 1095601
6 119621653
7 17943752233
8 3550217905597
9 894951415465441
10 280109128908963493
11 106563994919500072153
12 48431841090878234155597
13 25916389944261925021739281
14 16128299505539619187866596533
15 11549663940282035980807700520073

List of values

[1, 1, 13, 313, 14797, 1095601, 119621653, 17943752233, 3550217905597, 894951415465441, 280109128908963493, 106563994919500072153, 48431841090878234155597, 25916389944261925021739281, 16128299505539619187866596533, 11549663940282035980807700520073]

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

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