A231378 Number of nX4 0..1 arrays with no element less than a strict majority of its horizontal and vertical neighbors.

7, 48, 378, 2539, 17363, 120124, 830890, 5746499, 39745115, 274872588, 1900931060, 13146313579, 90916738809, 628758673194, 4348344850906, 30072109222833, 207971483025113, 1438280832129012, 9946804915649296, 68789714754091787

Offset: 1

Author

R. H. Hardin, Nov 08 2013

Keywords

• nonn

Comments

Column 4 of A231382

Examples

			Some solutions for n=3
..0..1..0..0....0..0..0..0....0..0..1..1....0..0..0..0....0..0..0..1
..0..0..0..0....1..0..0..1....0..0..0..0....0..0..0..0....1..0..0..1
..0..1..1..1....0..0..0..0....1..1..1..0....0..0..0..1....1..1..0..0
		

Links

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

Formula

Empirical: a(n) = 10*a(n-1) -31*a(n-2) +82*a(n-3) -131*a(n-4) +226*a(n-5) -319*a(n-6) +206*a(n-7) -574*a(n-8) +483*a(n-9) -432*a(n-10) +517*a(n-11) +132*a(n-12) +746*a(n-13) -145*a(n-14) -228*a(n-15) -6*a(n-16) +41*a(n-17) +3*a(n-18) -3*a(n-19) for n>20