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.

A221568 Number of 0..3 arrays of length n with each element differing from at least one neighbor by something other than 1.

Table of values

n a(n)
1 0
2 10
3 26
4 100
5 342
6 1210
7 4240
8 14898
9 52306
10 183684
11 645006
12 2264978
13 7953568
14 27929338
15 98075178
16 344395620
17 1209361446
18 4246729738
19 14912591664
20 52366268642
21 183886620962
22 645726538244
23 2267499179678
24 7962430263202
25 27960449231680
26 98184435580010

List of values

[0, 10, 26, 100, 342, 1210, 4240, 14898, 52306, 183684, 645006, 2264978, 7953568, 27929338, 98075178, 344395620, 1209361446, 4246729738, 14912591664, 52366268642, 183886620962, 645726538244, 2267499179678, 7962430263202, 27960449231680, 98184435580010]

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

Content is available under The OEIS End-User License Agreement.