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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A230983 Number of white square subarrays of (n+1) X (2+1) binary arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors, with upper left element zero. 1
 1, 1, 4, 5, 15, 20, 57, 77, 218, 295, 835, 1130, 3199, 4329, 12256, 16585, 46955, 63540, 179893, 243433, 689202, 932635, 2640455, 3573090, 10116051, 13689141, 38756384, 52445525, 148482575, 200928100, 568863057, 769791157, 2179415178, 2949206335 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 5*a(n-2) - 5*a(n-4) + 2*a(n-6). Empirical g.f.: x*(1 + x - x^2) / (1 - 5*x^2 + 5*x^4 - 2*x^6). - Colin Barker, Sep 25 2018 EXAMPLE Some solutions for n=6: ..0..x..0....0..x..0....0..x..0....0..x..0....0..x..0....0..x..0....0..x..0 ..x..1..x....x..1..x....x..1..x....x..1..x....x..1..x....x..1..x....x..1..x ..0..x..0....0..x..0....0..x..0....1..x..0....0..x..1....1..x..1....0..x..1 ..x..0..x....x..0..x....x..1..x....x..0..x....x..0..x....x..0..x....x..0..x ..1..x..1....1..x..1....1..x..1....1..x..0....1..x..0....1..x..0....1..x..1 ..x..1..x....x..0..x....x..0..x....x..1..x....x..1..x....x..1..x....x..0..x ..0..x..0....1..x..1....1..x..1....0..x..0....0..x..0....0..x..0....1..x..1 CROSSREFS Column 2 of A230989. Sequence in context: A066516 A047184 A002509 * A100234 A007390 A037955 Adjacent sequences: A230980 A230981 A230982 * A230984 A230985 A230986 KEYWORD nonn AUTHOR R. H. Hardin, Nov 02 2013 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 February 22 19:58 EST 2024. Contains 370260 sequences. (Running on oeis4.)