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.

A209220 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically.

Table of values

n a(n)
1 9
2 81
3 100
4 196
5 324
6 576
7 1024
8 1764
9 3136
10 5476
11 9604
12 16900
13 29584
14 51984
15 91204
16 160000
17 280900
18 492804
19 864900
20 1517824
21 2663424
22 4674244
23 8202496
24 14394436
25 25260676
26 44328964
27 77792400
28 136515856
29 239568484
30 420414016
31 737774244

List of values

[9, 81, 100, 196, 324, 576, 1024, 1764, 3136, 5476, 9604, 16900, 29584, 51984, 91204, 160000, 280900, 492804, 864900, 1517824, 2663424, 4674244, 8202496, 14394436, 25260676, 44328964, 77792400, 136515856, 239568484, 420414016, 737774244]

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

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