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.

A204707 Number of (n+1) X 3 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero.

Table of values

n a(n)
1 13
2 33
3 81
4 209
5 529
6 1361
7 3473
8 8913
9 22801
10 58449
11 149649
12 383441
13 982033
14 2515793
15 6443921
16 16507089
17 42282769
18 108311121
19 277442193
20 710686673
21 1820455441
22 4663202129
23 11945023889
24 30597832401
25 78377927953
26 200769257553

List of values

[13, 33, 81, 209, 529, 1361, 3473, 8913, 22801, 58449, 149649, 383441, 982033, 2515793, 6443921, 16507089, 42282769, 108311121, 277442193, 710686673, 1820455441, 4663202129, 11945023889, 30597832401, 78377927953, 200769257553]

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

Content is available under The OEIS End-User License Agreement.