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.

A227023 Number of nX4 (0,1,2) arrays of permanents of 2X2 subblocks of some (n+1)X5 binary array with rows and columns of the latter in lexicographically nondecreasing order.

Table of values

n a(n)
1 18
2 171
3 1366
4 10050
5 65317
6 375270
7 1924848
8 8908719
9 37616613
10 146387460
11 529743352
12 1796459014
13 5746888515
14 17440783714
15 50456503591
16 139731086307
17 371756133099
18 953183208702
19 2361809765393
20 5669196636680
21 13211336518266

List of values

[18, 171, 1366, 10050, 65317, 375270, 1924848, 8908719, 37616613, 146387460, 529743352, 1796459014, 5746888515, 17440783714, 50456503591, 139731086307, 371756133099, 953183208702, 2361809765393, 5669196636680, 13211336518266]

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

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