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.

A203650 1/25 the number of (n+1) X 3 0..4 arrays with every 2 X 2 subblock having equal diagonal elements or equal antidiagonal elements.

Table of values

n a(n)
1 81
2 1517
3 28057
4 519445
5 9616161
6 178019197
7 3295578857
8 61009378085
9 1129435635441
10 20908668388877
11 387071560403257
12 7165659241743925
13 132654210800937921
14 2455760042384774557
15 45462238622967429257

List of values

[81, 1517, 28057, 519445, 9616161, 178019197, 3295578857, 61009378085, 1129435635441, 20908668388877, 387071560403257, 7165659241743925, 132654210800937921, 2455760042384774557, 45462238622967429257]

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

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