A208687 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 0 1 vertically

42, 1764, 7086, 40581, 269766, 1346961, 6398617, 31733422, 152209092, 711191700, 3333256899, 15574230936, 72263776797, 334784881455, 1550207903794, 7167239737000, 33109416636066, 152910959100921, 705957016908150

Offset

1,1

Comments

Column 7 of A208688

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -7*a(n-2) +31*a(n-3) -128*a(n-4) -30*a(n-5) -116*a(n-6) +788*a(n-7) +798*a(n-8) +678*a(n-9) -2778*a(n-10) -1872*a(n-11) -1842*a(n-12) +3336*a(n-13) +1554*a(n-14) +378*a(n-15) -2736*a(n-16) +912*a(n-17) +312*a(n-18) +1590*a(n-19) -540*a(n-20) -228*a(n-21) -222*a(n-22) +210*a(n-23) -86*a(n-24) +24*a(n-25) -38*a(n-26) +8*a(n-27) -a(n-28) -a(n-30) +a(n-31)

Example

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

Crossrefs

Sequence in context: A207933 A207850 A208839 * A207351 A207773 A207900

Adjacent sequences: A208684 A208685 A208686 * A208688 A208689 A208690

Keyword

nonn

Author

R. H. Hardin Mar 01 2012

Status

approved