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.

A259215 Number of (n+1) X (1+1) 0..1 arrays with each 2 X 2 subblock having clockwise pattern 0000 0011 or 0101.

Table of values

n a(n)
1 7
2 13
3 24
4 45
5 85
6 162
7 311
8 601
9 1168
10 2281
11 4473
12 8802
13 17371
14 34365
15 68120
16 135253
17 268909
18 535234
19 1066287
20 2125809
21 4240672
22 8463633
23 16898609
24 33750850
25 67426675
26 134731957
27 269267496
28 538217181
29 1075920133
30 2151008226
31 4300670183

List of values

[7, 13, 24, 45, 85, 162, 311, 601, 1168, 2281, 4473, 8802, 17371, 34365, 68120, 135253, 268909, 535234, 1066287, 2125809, 4240672, 8463633, 16898609, 33750850, 67426675, 134731957, 269267496, 538217181, 1075920133, 2151008226, 4300670183]

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

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