A183806 1/16 the number of (n+1)X5 binary arrays with no 2X2 subblock being a reflection across the shared element pair of any horizontal or vertical neighbor

27, 237, 1953, 16953, 143191, 1232595, 10494847, 89998565, 768481445, 6579905737, 56244325315, 481279798699, 4115586970547, 35208336763197, 301125201891953, 2575843502271345, 22031666094964551, 188453144399278867

Offset

1,1

Comments

Column 4 of A183811

Links

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

Formula

Empirical: a(n)=6*a(n-1)+81*a(n-2)-425*a(n-3)-1968*a(n-4)+10277*a(n-5)+16576*a(n-6)-92864*a(n-7)-64803*a(n-8)+320262*a(n-9)+224743*a(n-10)-99955*a(n-11)-959780*a(n-12)-1547921*a(n-13)+2262032*a(n-14)+2523060*a(n-15)-1692000*a(n-16)-1053000*a(n-17)

Example

Some solutions with upper left block zero for 3X5
..0..0..1..0..0....0..0..1..0..1....0..0..1..1..1....0..0..0..1..1
..0..0..1..1..0....0..0..1..1..0....0..0..1..1..0....0..0..1..0..0
..0..1..0..1..1....1..1..0..0..0....0..1..0..1..0....0..1..1..0..1

Crossrefs

Sequence in context: A273822 A027500 A069979 * A207104 A075548 A345054

Adjacent sequences: A183803 A183804 A183805 * A183807 A183808 A183809

Keyword

nonn

Author

R. H. Hardin Jan 07 2011

Status

approved