A269078 Number of 4 X n binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

16, 89, 537, 3288, 17713, 102545, 542112, 2991561, 15699273, 84015848, 437869217, 2298582593, 11896438960, 61665786297, 317089210745, 1629210973432, 8329629544721, 42518834195697, 216316340106688, 1098583548812969

Offset

1,1

Links

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

Formula

Empirical: a(n) = 4*a(n-1) + 28*a(n-2) - 78*a(n-3) - 264*a(n-4) + 296*a(n-5) + 527*a(n-6) - 252*a(n-7) - 324*a(n-8).

Empirical g.f.: x*(16 + 25*x - 267*x^2 - 104*x^3 + 691*x^4 + 275*x^5 - 576*x^6 - 324*x^7) / (1 - 2*x - 16*x^2 + 7*x^3 + 18*x^4)^2. - Colin Barker, Jan 19 2019

Example

Some solutions for n=4:
..0..1..0..1. .1..0..1..0. .0..0..0..1. .0..0..0..1. .0..0..1..1
..0..1..0..1. .0..0..0..1. .1..0..0..1. .0..0..0..1. .1..0..0..0
..0..0..0..1. .1..0..0..0. .0..0..0..0. .0..1..0..0. .1..0..1..0
..1..1..0..1. .0..0..0..1. .0..1..0..0. .0..0..0..0. .0..0..1..0

Crossrefs

Row 4 of A269075.

Sequence in context: A301888 A302084 A229399 * A240262 A264531 A192129

Adjacent sequences: A269075 A269076 A269077 * A269079 A269080 A269081

Keyword

nonn

Author

R. H. Hardin, Feb 19 2016

Status

approved