A183340 Number of nX8 binary arrays with each 1 adjacent to exactly one 1 vertically and one 1 horizontally

1, 19, 63, 193, 1005, 4133, 16029, 68662, 286079, 1170324, 4869491, 20218182, 83588667, 346493199, 1436419555, 5949727953, 24653341080, 102162618558, 423291469427, 1753914307948, 7267558737304, 30113168208503, 124774750283399

Offset

1,2

Comments

Equivalent to all 1s connected only in 2X2 blocks

Column 8 of A183342

Links

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

Formula

Empirical: a(n)=a(n-1)+4*a(n-2)+33*a(n-3)+40*a(n-4)-27*a(n-5)-190*a(n-6)-384*a(n-7)+149*a(n-8)+768*a(n-9)+398*a(n-10)-281*a(n-11)+312*a(n-12)-879*a(n-13)-1871*a(n-14)+351*a(n-15)+2551*a(n-16)-928*a(n-17)+499*a(n-18)+267*a(n-19)-947*a(n-20)-295*a(n-21)-55*a(n-22)+284*a(n-23)+192*a(n-24)+136*a(n-25)+98*a(n-26)-86*a(n-27)+17*a(n-28)-4*a(n-29)-19*a(n-30)+3*a(n-31)-12*a(n-32)

Example

Some solutions for 5X8
..0..1..1..0..0..1..1..0....1..1..0..0..0..0..0..0....1..1..0..0..0..0..0..0
..0..1..1..0..0..1..1..0....1..1..0..1..1..0..0..0....1..1..0..0..0..0..0..0
..0..0..0..0..0..0..0..0....0..0..0..1..1..0..0..0....0..0..0..0..0..0..0..0
..0..1..1..0..0..0..1..1....1..1..0..0..0..1..1..0....1..1..0..0..1..1..0..0
..0..1..1..0..0..0..1..1....1..1..0..0..0..1..1..0....1..1..0..0..1..1..0..0

Crossrefs

Sequence in context: A214150 A262920 A183455 * A195749 A093485 A226633

Adjacent sequences: A183337 A183338 A183339 * A183341 A183342 A183343

Keyword

nonn

Author

R. H. Hardin Jan 04 2011

Status

approved