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.

A266682 Number of 3Xn arrays containing n copies of 0..3-1 with no element 1 greater than its northwest or northeast neighbor modulo 3 and the upper left element equal to 0.

Table of values

n a(n)
1 2
2 5
3 15
4 59
5 257
6 1205
7 5879
8 29693
9 153097
10 806375
11 4307317
12 23313947
13 127420533
14 702562447
15 3900415155
16 21786817517
17 122309555899
18 689707853981
19 3904123962093
20 22174631940293
21 126322762595339
22 721552901977497

List of values

[2, 5, 15, 59, 257, 1205, 5879, 29693, 153097, 806375, 4307317, 23313947, 127420533, 702562447, 3900415155, 21786817517, 122309555899, 689707853981, 3904123962093, 22174631940293, 126322762595339, 721552901977497]

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

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