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.

A180763 Half the number of n X 3 binary arrays with each element equal to at least one neighbor.

Table of values

n a(n)
1 1
2 11
3 63
4 390
5 2385
6 14621
7 89602
8 549125
9 3365327
10 20624430
11 126397089
12 774626021
13 4747304792
14 29093913597
15 178302394173
16 1092728334730
17 6696798543441
18 41041409200977
19 251522762447718
20 1541460229095645

List of values

[1, 11, 63, 390, 2385, 14621, 89602, 549125, 3365327, 20624430, 126397089, 774626021, 4747304792, 29093913597, 178302394173, 1092728334730, 6696798543441, 41041409200977, 251522762447718, 1541460229095645]

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

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