A203361 Number of nX7 binary arrays with every 1 immediately preceded by 0 to the left or above.

21, 1640, 89610, 5390325, 314688054, 18550312526, 1089970014327, 64114204398028, 3769915844080995, 221699388876599524, 13037021233036033635, 766652822812020772883, 45083423150083817466414, 2651159090798112000786121

Offset: 1

Author

R. H. Hardin Dec 31 2011

Keywords

• nonn

Comments

Column 7 of A203362

Examples

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

Links

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

Formula

Empirical: a(n) = 21*a(n-1) +1743*a(n-2) +25515*a(n-3) +156938*a(n-4) +213951*a(n-5) -1636533*a(n-6) -3128592*a(n-7) [phone]*a(n-8) [phone]*a(n-9) -199519590*a(n-10) [phone]*a(n-11) -22194350*a(n-12) -173766021*a(n-13) [phone]*a(n-14) -33578772*a(n-15) -2885164*a(n-16) +4086456*a(n-17) -689631*a(n-18) -24273*a(n-19) +4320*a(n-20) for n>21