A240779 Number of nX4 0..1 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..1 introduced in row major order.

1, 6, 46, 305, 2167, 15332, 108509, 767834, 5434887, 38467875, 272273018, 1927138748, 13640213436, 96544878838, 683340799760, 4836658942731, 34233678967243, 242304613789940, 1715022389014131, 12138860042126682

Offset: 1

Author

R. H. Hardin, Apr 12 2014

Keywords

• nonn

Comments

Column 4 of A240783

Examples

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

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +2*a(n-2) -7*a(n-3) -25*a(n-4) -6*a(n-5) +150*a(n-6) +12*a(n-7) -456*a(n-8) -134*a(n-9) +408*a(n-10) +116*a(n-11) -171*a(n-12) +73*a(n-13) +388*a(n-14) +87*a(n-15) -127*a(n-16) -168*a(n-17) -62*a(n-18) -12*a(n-19) +16*a(n-20) +8*a(n-21) +2*a(n-22)