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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.

A222821 T(n,k)=Number of idempotent n X n 0..k matrices.

Table of values

n a(n)
1 2
2 2
3 8
4 2
5 12
6 50
7 2
8 16
9 122
10 452
11 2
12 20
13 218
14 2052
15 5682
16 2
17 24
18 344
19 5584
20 54182
21 96608
22 2
23 28
24 488
25 12476
26 248442
27 2236302
28 2185738
29 2
30 32
31 668
32 23568
33 855192
34 20394466
35 145121216
36 65108492
37 2
38 36
39 860
40 41668
41 2319872
42 126252320

List of values

[2, 2, 8, 2, 12, 50, 2, 16, 122, 452, 2, 20, 218, 2052, 5682, 2, 24, 344, 5584, 54182, 96608, 2, 28, 488, 12476, 248442, 2236302, 2185738, 2, 32, 668, 23568, 855192, 20394466, 145121216, 65108492, 2, 36, 860, 41668, 2319872, 126252320]

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

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