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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.

A069727 Number of nonisomorphic unrooted Eulerian planar maps with n edges (Eulerian means that all vertices are of even valency; there is an Eulerian cycle).

Table of values

n a(n)
0 1
1 1
2 2
3 4
4 12
5 34
6 154
7 675
8 3534
9 18985
10 108070
11 632109
12 3807254
13 23411290
14 146734695
15 934382820
16 6034524474
17 39457153432
18 260855420489
19 1741645762265
20 11732357675908
21 79673115468562
22 545036528857605
23 3753642607424647
24 26010818244754788
25 181266500331748878

List of values

[1, 1, 2, 4, 12, 34, 154, 675, 3534, 18985, 108070, 632109, 3807254, 23411290, 146734695, 934382820, 6034524474, 39457153432, 260855420489, 1741645762265, 11732357675908, 79673115468562, 545036528857605, 3753642607424647, 26010818244754788, 181266500331748878]

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

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