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.

A139670 Number of n X n symmetric binary matrices with all row sums 4.

Table of values

n a(n)
4 1
5 26
6 820
7 35150
8 1944530
9 133948836
10 11234051976
11 1127512146540
12 133475706272700
13 18406586045919060
14 2925154024273348296
15 530686776655470875076
16 109004840145995702773410
17 25164525076896596670014400
18 6486836210471246515195539840
19 1856264107759263993451053077856

List of values

[1, 26, 820, 35150, 1944530, 133948836, 11234051976, 1127512146540, 133475706272700, 18406586045919060, 2925154024273348296, 530686776655470875076, 109004840145995702773410, 25164525076896596670014400, 6486836210471246515195539840, 1856264107759263993451053077856]

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

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