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.

A262326 Number of (n+1) X (2+1) 0..1 arrays with each row and column divisible by 3, read as a binary number with top and left being the most significant bits.

Table of values

n a(n)
1 3
2 5
3 15
4 33
5 99
6 261
7 783
8 2241
9 6723
10 19845
11 59535
12 177633
13 532899
14 1595781
15 4787343
16 14353281
17 43059843
18 129153285
19 387459855
20 1162300833
21 3486902499
22 10460471301
23 31381413903
24 94143533121
25 282430599363
26 847289672325

List of values

[3, 5, 15, 33, 99, 261, 783, 2241, 6723, 19845, 59535, 177633, 532899, 1595781, 4787343, 14353281, 43059843, 129153285, 387459855, 1162300833, 3486902499, 10460471301, 31381413903, 94143533121, 282430599363, 847289672325]

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

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