A185568 Number of (n+1)X2 0..3 arrays with every 2X2 subblock sum equal to some horizontal or vertical neighbor 2X2 subblock sum

0, 704, 1936, 34816, 172992, 2053216, 12950528, 131772320, 929033280, 8815545344, 65895014896, 602776037920, 4662229953024, 41734072588384, 329907085742480, 2911856599577984, 23363245790844864, 204187515832240736

Offset

1,2

Comments

Column 1 of A185571

Links

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

Formula

Empirical: a(n)=10*a(n-1)+60*a(n-2)-864*a(n-3)+1955*a(n-4)+8606*a(n-5)-114460*a(n-6)+519812*a(n-7)-967685*a(n-8)-601250*a(n-9)+29248052*a(n-10)-142231024*a(n-11)+606947468*a(n-12)-1737563336*a(n-13)+2990726160*a(n-14)-1186538304*a(n-15)-43406163408*a(n-16)+180796251360*a(n-17)-851333675072*a(n-18)+2254070076672*a(n-19)-7178768320512*a(n-20)+14997302931456*a(n-21)-37689333792768*a(n-22)+64400381116416*a(n-23)-132751562784768*a(n-24)+185092667965440*a(n-25)-315476853719040*a(n-26)+350433362313216*a(n-27)-486487023943680*a(n-28)+399408277487616*a(n-29)-425165901004800*a(n-30)+204079632482304*a(n-31)-142657607172096*a(n-32)

Example

Some solutions for 3X2
..0..3....1..1....2..0....1..0....0..0....3..0....2..0....2..2....2..1....0..3
..3..1....1..1....0..3....3..1....2..0....1..2....1..2....1..0....0..3....3..1
..1..2....2..0....1..1....0..1....0..0....1..2....0..2....3..1....2..1....3..0

Crossrefs

Sequence in context: A105846 A323342 A237009 * A185799 A186916 A185800

Adjacent sequences: A185565 A185566 A185567 * A185569 A185570 A185571

Keyword

nonn

Author

R. H. Hardin Jan 31 2011

Status

approved