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.

A297683 Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 1 or 4 neighboring 1s.

Original entry on oeis.org

8, 33, 150, 629, 2790, 12110, 52889, 230406, 1005170, 4382278, 19110183, 83327912, 363357551, 1584416863, 6908888883, 30126285845, 131366174343, 572824066436, 2497808102429, 10891729292407, 47493549245614, 207096331298600
Offset: 1

Views

Author

R. H. Hardin, Jan 03 2018

Keywords

Comments

Row 3 of A297682.

Examples

			Some solutions for n=7
..0..1..0..0..0..0..1. .0..0..0..1..0..0..0. .0..0..1..0..0..0..1
..1..0..0..0..0..1..1. .0..0..0..1..0..0..0. .1..0..0..0..0..0..0
..0..0..0..0..1..0..1. .0..0..0..0..1..0..1. .1..0..1..1..0..0..1
		

Crossrefs

Cf. A297682.

Formula

Empirical: a(n) = 2*a(n-1) +7*a(n-2) +11*a(n-3) +17*a(n-4) -7*a(n-5) -10*a(n-6) -18*a(n-7) -a(n-8)