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.

A223095 Number of foldings of n labeled stamps in which both end leaves are inwards.

Table of values

n a(n)
1 0
2 0
3 0
4 2
5 10
6 40
7 156
8 546
9 1986
10 6716
11 23742
12 79472
13 277178
14 925588
15 3205896
16 10711486
17 36963722
18 123712788
19 426075994
20 1429030624
21 4916833424
22 16526958144
23 56840484232
24 191466923584
25 658460090994
26 2222507917328
27 7644360501390
28 25850724646008
29 88938175307354

List of values

[0, 0, 0, 2, 10, 40, 156, 546, 1986, 6716, 23742, 79472, 277178, 925588, 3205896, 10711486, 36963722, 123712788, 426075994, 1429030624, 4916833424, 16526958144, 56840484232, 191466923584, 658460090994, 2222507917328, 7644360501390, 25850724646008, 88938175307354]

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

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