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.

A108798 Number of nonisomorphic systems enumerated by A102894; that is, the number of inequivalent closure operators in which the empty set is closed. Also, the number of union-closed sets with n elements that contain the universe and the empty set.

Table of values

n a(n)
0 1
1 1
2 3
3 14
4 165
5 14480
6 108281182
7 2796163091470050

List of values

[1, 1, 3, 14, 165, 14480, 108281182, 2796163091470050]

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

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