The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A283124 Number of nX2 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors. 3
 4, 16, 57, 209, 768, 2816, 10329, 37889, 138980, 509792, 1869969, 6859233, 25160352, 92290688, 338531473, 1241767297, 4554926628, 16707926384, 61286344841, 224804441777, 824605173856, 3024734241792, 11095027685417, 40697671100929 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 2 of A283130. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 3*a(n-1) +2*a(n-2) +2*a(n-3) -a(n-4) -a(n-5). Empirical: G.f.: -x*(x+2)*(x^3-x-2)/(1-3*x-2*x^2-2*x^3+x^4+x^5) . - R. J. Mathar, Mar 02 2017 EXAMPLE Some solutions for n=4 ..0..1. .1..1. .1..1. .1..0. .1..0. .1..1. .1..0. .0..1. .0..0. .1..0 ..1..1. .0..0. .0..0. .0..1. .1..1. .1..0. .0..1. .0..1. .0..1. .0..0 ..0..0. .1..1. .0..1. .0..0. .0..0. .1..0. .1..0. .1..0. .1..1. .1..0 ..1..1. .0..1. .1..1. .0..1. .0..0. .1..1. .0..1. .1..0. .0..0. .1..0 CROSSREFS Cf. A283130. Sequence in context: A197674 A297220 A297375 * A282393 A034514 A263851 Adjacent sequences: A283121 A283122 A283123 * A283125 A283126 A283127 KEYWORD nonn AUTHOR R. H. Hardin, Mar 01 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified March 20 22:04 EDT 2023. Contains 361391 sequences. (Running on oeis4.)