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.

A132581 Number of antichains in the first n elements of the infinite Boolean lattice.

Table of values

n a(n)
0 1
1 2
2 3
3 5
4 6
5 11
6 14
7 19
8 20
9 39
10 53
11 78
12 84
13 134
14 148
15 167
16 168
17 335
18 483
19 765
20 849
21 1466
22 1681
23 1988
24 2008
25 3700
26 4414
27 5489
28 5573
29 7265
30 7413
31 7580
32 7581
33 15161
34 22574
35 37252
36 42825
37 77388
38 92864
39 116454
40 118462
41 227503
42 286776
43 382574
44 392247
45 555662
46 574114
47 595481
48 595649
49 1176304
50 1563955

List of values

[1, 2, 3, 5, 6, 11, 14, 19, 20, 39, 53, 78, 84, 134, 148, 167, 168, 335, 483, 765, 849, 1466, 1681, 1988, 2008, 3700, 4414, 5489, 5573, 7265, 7413, 7580, 7581, 15161, 22574, 37252, 42825, 77388, 92864, 116454, 118462, 227503, 286776, 382574, 392247, 555662, 574114, 595481, 595649, 1176304, 1563955]

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

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