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.

A233021 Number of n X 3 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, vertically, diagonally or antidiagonally, and top left element zero.

Table of values

n a(n)
1 9
2 81
3 849
4 8835
5 92067
6 959385
7 9997413
8 104179551
9 1085618895
10 11312857317
11 117887355777
12 1228463178219
13 12801387988827
14 133398816787089
15 1390102724464989
16 14485777543658775
17 150951255149241255

List of values

[9, 81, 849, 8835, 92067, 959385, 9997413, 104179551, 1085618895, 11312857317, 117887355777, 1228463178219, 12801387988827, 133398816787089, 1390102724464989, 14485777543658775, 150951255149241255]

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

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