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.

A035309 Triangle read by rows giving number of ways to glue sides of a 2n-gon so as to produce a surface of genus g.

Table of values

n a(n)
0 1
1 1
2 2
3 1
4 5
5 10
6 14
7 70
8 21
9 42
10 420
11 483
12 132
13 2310
14 6468
15 1485
16 429
17 12012
18 66066
19 56628
20 1430
21 60060
22 570570
23 1169740
24 225225
25 4862
26 291720
27 4390386
28 17454580
29 12317877
30 16796
31 1385670
32 31039008
33 211083730
34 351683046
35 59520825
36 58786
37 6466460
38 205633428
39 2198596400
40 7034538511
41 4304016990

List of values

[1, 1, 2, 1, 5, 10, 14, 70, 21, 42, 420, 483, 132, 2310, 6468, 1485, 429, 12012, 66066, 56628, 1430, 60060, 570570, 1169740, 225225, 4862, 291720, 4390386, 17454580, 12317877, 16796, 1385670, 31039008, 211083730, 351683046, 59520825, 58786, 6466460, 205633428, 2198596400, 7034538511, 4304016990]

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

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