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.

A259421 Number of (n+1) X (2+1) 0..1 arrays with each 2 X 2 subblock having clockwise pattern 0000 0001 0011 or 0111.

Table of values

n a(n)
1 43
2 243
3 1366
4 7695
5 43347
6 244228
7 1376077
8 7753553
9 43687910
10 246163281
11 1387029593
12 7815349472
13 44036333771
14 248126951851
15 1398095180302
16 7877701886559
17 44387669863035
18 250106600625676
19 1409249728938893

List of values

[43, 243, 1366, 7695, 43347, 244228, 1376077, 7753553, 43687910, 246163281, 1387029593, 7815349472, 44036333771, 248126951851, 1398095180302, 7877701886559, 44387669863035, 250106600625676, 1409249728938893]

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

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