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.

A301947 Number of nX4 0..1 arrays with every element equal to 1, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 2
2 16
3 123
4 947
5 7326
6 56710
7 439078
8 3399722
9 26323903
10 203825456
11 1578217598
12 12220118582
13 94620225492
14 732643232114
15 5672847473255
16 43924787764759
17 340109088005893
18 2633460459021237
19 20390851741033347
20 157886112662767667

List of values

[2, 16, 123, 947, 7326, 56710, 439078, 3399722, 26323903, 203825456, 1578217598, 12220118582, 94620225492, 732643232114, 5672847473255, 43924787764759, 340109088005893, 2633460459021237, 20390851741033347, 157886112662767667]

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

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