A228666 Number of 7 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally.

64, 169, 9598, 63688, 1720343, 17074988, 337258048, 4073313193, 69400592022, 925095934000, 14659747315671, 205401189207844, 3139657337791256, 45112454177593993, 677231112691330078, 9855259627789459448

Offset: 1

Author

R. H. Hardin, Aug 29 2013

Keywords

• nonn

Comments

Row 7 of A228660.

Examples

			Some solutions for n=4
..1..0..0..1....1..0..0..1....1..0..0..0....1..0..0..0....1..0..0..0
..1..0..0..1....1..0..0..0....0..0..1..0....1..0..0..0....1..0..0..1
..0..0..0..0....0..0..0..1....1..0..0..0....0..0..0..1....0..0..0..0
..0..0..0..0....1..0..0..1....1..0..1..0....1..0..0..0....0..1..0..0
..0..0..0..0....0..0..0..0....1..0..0..0....0..0..0..1....0..1..0..0
..0..0..0..1....0..1..0..0....0..0..0..1....0..0..0..1....0..0..0..1
..1..0..0..1....0..1..0..0....1..0..0..0....0..0..0..1....1..0..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A228660.

Formula

Empirical: a(n) = 9*a(n-1) +184*a(n-2) -1201*a(n-3) -7155*a(n-4) +46048*a(n-5) +70745*a(n-6) -591673*a(n-7) -154744*a(n-8) +3207657*a(n-9) -715173*a(n-10) -7580648*a(n-11) +3369552*a(n-12) +7114920*a(n-13) -3800952*a(n-14) -1923264*a(n-15) +1083456*a(n-16).