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.

A230185 Number of 2 X n 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value 2-x(i,j).

Table of values

n a(n)
1 0
2 9
3 27
4 159
5 825
6 4395
7 23307
8 123729
9 656715
10 3485775
11 18502017
12 98206299
13 521266155
14 2766812505
15 14685878427
16 77950719519
17 413752211145
18 2196142553835
19 11656837079787
20 61872964697889
21 328413594039435
22 1743176349744015

List of values

[0, 9, 27, 159, 825, 4395, 23307, 123729, 656715, 3485775, 18502017, 98206299, 521266155, 2766812505, 14685878427, 77950719519, 413752211145, 2196142553835, 11656837079787, 61872964697889, 328413594039435, 1743176349744015]

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

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