A251264 Number of (n+1)X(4+1) 0..1 arrays with no 2X2 subblock having x11-x00 less than x10-x01.

120, 772, 4930, 32636, 217634, 1457326, 9772880, 65582500, 440223510, 2955392154, 19841767762, 133216123406, 894412534702, 6005113336592, 40318603143004, 270701212074848, 1817502901804920, 12202817537105258, 81930416102796122

Offset: 1

Author

R. H. Hardin, Dec 01 2014

Keywords

• nonn

Comments

Column 4 of A251268

Examples

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

Links

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

Formula

Empirical: a(n) = 10*a(n-1) -11*a(n-2) -119*a(n-3) +288*a(n-4) +236*a(n-5) -1082*a(n-6) +141*a(n-7) +1550*a(n-8) -732*a(n-9) -936*a(n-10) +648*a(n-11) +181*a(n-12) -198*a(n-13) +14*a(n-14) +13*a(n-15) -2*a(n-16)