A207943 Number of 7Xn 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically.

14, 196, 826, 3641, 20568, 120276, 737575, 4570122, 28555126, 178852957, 1121957980, 7041891730, 44211129243, 277603005560, 1743182466528, 10946427636013, 68739662962482, 431662923010836, 2710711178183705

Offset: 1

Author

R. H. Hardin Feb 21 2012

Keywords

• nonn

Comments

Row 7 of A207938

Examples

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

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -12*a(n-2) -210*a(n-3) +495*a(n-4) +1675*a(n-5) -4933*a(n-6) -7524*a(n-7) +24432*a(n-8) +22034*a(n-9) -69076*a(n-10) -45806*a(n-11) +114911*a(n-12) +67305*a(n-13) -109800*a(n-14) -63536*a(n-15) +56149*a(n-16) +33715*a(n-17) -13209*a(n-18) -8384*a(n-19) +1044*a(n-20) +720*a(n-21) for n>22