A208373 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically.

31, 961, 11067, 177909, 2563359, 38542393, 570085195, 8487780687, 126039261499, 1873614472027, 27839846618695, 413742327695195, 6148396146149603, 91370604275750753, 1357831649082497201, 20178435819755002559

Offset: 1

Author

R. H. Hardin Feb 25 2012

Keywords

• nonn

Comments

Row 7 of A208369

Examples

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

Links

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

Formula

Empirical: a(n) = 178*a(n-2) +932*a(n-3) -2956*a(n-4) -23754*a(n-5) +20253*a(n-6) +256486*a(n-7) -113835*a(n-8) -1502278*a(n-9) +783938*a(n-10) +4923968*a(n-11) -3657059*a(n-12) -8430388*a(n-13) +8233841*a(n-14) +6798200*a(n-15) -8443642*a(n-16) -2506050*a(n-17) +4235409*a(n-18) +420518*a(n-19) -1084169*a(n-20) -45082*a(n-21) +134907*a(n-22) +7426*a(n-23) -6196*a(n-24) -610*a(n-25)