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.

A203094 Number of nX1 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

Table of values

n a(n)
1 1
2 4
3 16
4 50
5 144
6 422
7 1268
8 3823
9 11472
10 34350
11 102896
12 308419
13 924532
14 2771101
15 8305373
16 24892609
17 74608516
18 223618304
19 670231838
20 2008825312
21 6020872062
22 18045827096
23 54087163859
24 162110668160
25 485879938474
26 1456284886944

List of values

[1, 4, 16, 50, 144, 422, 1268, 3823, 11472, 34350, 102896, 308419, 924532, 2771101, 8305373, 24892609, 74608516, 223618304, 670231838, 2008825312, 6020872062, 18045827096, 54087163859, 162110668160, 485879938474, 1456284886944]

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

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