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.

A262414 Number of (n+1) X (2+1) 0..1 arrays with each row divisible by 3 and column not divisible by 3, read as a binary number with top and left being the most significant bits.

Table of values

n a(n)
1 0
2 4
3 12
4 48
5 144
6 468
7 1404
8 4320
9 12960
10 39204
11 117612
12 353808
13 1061424
14 3187188
15 9561564
16 28693440
17 86080320
18 258267204
19 774801612
20 2324483568
21 6973450704
22 20920588308
23 62761764924
24 188286003360
25 564858010080
26 1694576156004

List of values

[0, 4, 12, 48, 144, 468, 1404, 4320, 12960, 39204, 117612, 353808, 1061424, 3187188, 9561564, 28693440, 86080320, 258267204, 774801612, 2324483568, 6973450704, 20920588308, 62761764924, 188286003360, 564858010080, 1694576156004]

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

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