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.

A109542 a(n) = number of labeled 3-regular (trivalent) multi-graphs without self-loops on 2n vertices with a maximum of 2 edges between any pair of nodes. Also a(n) = number of labeled symmetric 2n X 2n matrices with {0,1,2}-entries with row sum equal to 3 for each row and trace 0.

Table of values

n a(n)
1 0
2 7
3 640
4 170555
5 94949400
6 95830621425
7 159062872168200
8 404720953797785625

List of values

[0, 7, 640, 170555, 94949400, 95830621425, 159062872168200, 404720953797785625]

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

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