A208699 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 1 0 and 1 0 1 vertically.

10, 100, 358, 1309, 5524, 24086, 109599, 506870, 2376964, 11224757, 53273404, 253567712, 1209244939, 5773573436, 27587164014, 131879534567, 630640340412, 3016276415808, 14428300026213, 69023041742528, 330213969177428

Offset: 1

Author

R. H. Hardin Mar 01 2012

Keywords

• nonn

Comments

Row 4 of A208698

Examples

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

Links

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

Formula

Empirical: a(n) = 10*a(n-1) -19*a(n-2) -92*a(n-3) +320*a(n-4) +223*a(n-5) -1644*a(n-6) +308*a(n-7) +3927*a(n-8) -2262*a(n-9) -4540*a(n-10) +3797*a(n-11) +2137*a(n-12) -2578*a(n-13) -60*a(n-14) +622*a(n-15) -128*a(n-16) -28*a(n-17) +8*a(n-18) for n>19