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.

A208874 Number of 3Xn 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

Table of values

n a(n)
1 5
2 143
3 6520
4 307165
5 14493405
6 683903931
7 32271626438
8 1522813452263
9 71857577327143
10 3390770839381669
11 160001593732718856
12 7550056082308516761
13 356267369073405009281
14 16811323900505484274607
15 793282337427660173475274

List of values

[5, 143, 6520, 307165, 14493405, 683903931, 32271626438, 1522813452263, 71857577327143, 3390770839381669, 160001593732718856, 7550056082308516761, 356267369073405009281, 16811323900505484274607, 793282337427660173475274]

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

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