A301949 Number of nX6 0..1 arrays with every element equal to 1, 2 or 3 horizontally or antidiagonally adjacent elements, with upper left element zero.

5, 169, 4070, 98839, 2406169, 58609226, 1427656268, 34776685046, 847137052736, 20635714219606, 502672812882802, 12244789017184793, 298275250691010051, 7265794879094161325, 176990129491522032721, 4311366679215895257906

Offset: 1

Author

R. H. Hardin, Mar 29 2018

Keywords

• nonn

Comments

Column 6 of A301951.

Examples

			Some solutions for n=5
..0..0..1..1..0..1. .0..0..0..0..0..1. .0..0..1..1..1..0. .0..0..0..0..0..0
..0..0..0..0..1..0. .0..1..1..0..1..1. .0..0..0..1..0..0. .0..0..1..1..1..1
..0..1..1..0..0..0. .0..0..1..1..0..0. .0..1..1..1..1..0. .0..0..1..1..0..0
..0..0..1..1..0..0. .0..0..0..1..0..0. .0..0..1..1..0..0. .0..1..0..1..1..1
..0..1..0..0..1..1. .0..0..1..1..1..1. .0..1..1..0..1..1. .0..0..1..0..0..0
		

Links

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

Crossrefs

Cf. A301951.

Formula

Empirical: a(n) = 33*a(n-1) -194*a(n-2) -715*a(n-3) +7892*a(n-4) -2145*a(n-5) -104797*a(n-6) +126737*a(n-7) +639098*a(n-8) -780482*a(n-9) -2453736*a(n-10) +1736864*a(n-11) +5706799*a(n-12) -506462*a(n-13) -5848822*a(n-14) -644915*a(n-15) +3230474*a(n-16) +509931*a(n-17) -1056960*a(n-18) -144139*a(n-19) +202757*a(n-20) +17729*a(n-21) -20624*a(n-22) -825*a(n-23) +894*a(n-24) +25*a(n-25) -16*a(n-26) for n>28