A269273 Number of n X 5 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

432, 127512, 23549400, 3719884392, 542973139128, 75556007986536, 10181956012212600, 1340897428986116904, 173553231095580128184, 22161410569440812760552, 2799318884872209986120184

Offset: 1

Author

R. H. Hardin, Feb 21 2016

Keywords

• nonn

Examples

			Some solutions for n=2:
..2..2..3..1..1. .0..3..2..3..3. .2..2..3..0..1. .2..2..1..3..3
..0..2..2..3..1. .2..3..1..3..1. .0..2..0..0..2. .2..3..1..1..3
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Column 5 of A269276.

Formula

Empirical: a(n) = 234*a(n-1) - 14277*a(n-2) + 68796*a(n-3) - 86436*a(n-4).

Empirical g.f.: 72*x*(6 + 367*x - 1677*x^2 + 1302*x^3) / (1 - 117*x + 294*x^2)^2. - Colin Barker, Jan 21 2019