A187722 Number of (n+1)X3 binary arrays with no 2X2 subblock commuting with any of its horizontal and vertical 2X2 subblock neighbors

43, 174, 689, 2804, 11324, 46003, 186672, 758077, 3077859, 12497826, 50746523, 206054545, 836678679, 3397305868, 13794653865, 56012764479, 227438082864, 923505221937, 3749864236851, 15226206788800, 61825538083188

Offset

1,1

Comments

Column 2 of A187729

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=9*a(n-2)+31*a(n-3)+24*a(n-4)-60*a(n-5)-167*a(n-6)-146*a(n-7)+80*a(n-8)+321*a(n-9)+368*a(n-10)+29*a(n-11)-621*a(n-12)-250*a(n-13)+210*a(n-14)+167*a(n-15)+275*a(n-16)-76*a(n-17)-88*a(n-18)-54*a(n-19)-41*a(n-20)-16*a(n-21)+21*a(n-22)+14*a(n-23)-5*a(n-24)+a(n-25)+2*a(n-26)-a(n-27) for n>28

Example

Some solutions for 5X3
..0..1..1....0..1..0....1..1..1....1..0..1....0..1..0....1..1..1....0..0..1
..1..1..1....1..0..0....1..0..1....0..0..1....1..0..0....0..0..1....0..1..0
..0..0..1....1..1..1....1..0..1....1..0..0....1..1..1....0..1..1....1..1..1
..0..1..1....0..0..1....1..1..1....1..0..1....1..1..0....1..0..1....1..0..0
..1..0..1....1..1..0....0..1..1....1..1..0....1..0..0....1..1..0....1..1..1

Crossrefs

Sequence in context: A158604 A057816 A162295 * A158628 A123597 A138631

Adjacent sequences: A187719 A187720 A187721 * A187723 A187724 A187725

Keyword

nonn

Author

R. H. Hardin Mar 13 2011

Status

approved