A208839 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 1 and 1 1 0 vertically

42, 1764, 7086, 31419, 169974, 992574, 6206445, 40122936, 265568130, 1780946115, 12045557394, 81883111842, 558396389421, 3815311552572, 26099962612902, 178677791790795, 1223770846004094, 8384018150245206, 57448693695345549

Offset

1,1

Comments

Column 7 of A208840

Links

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

Formula

Empirical: a(n) = 11*a(n-1) -17*a(n-2) -124*a(n-3) +276*a(n-4) +396*a(n-5) -902*a(n-6) -462*a(n-7) +946*a(n-8) +220*a(n-9) -340*a(n-10) -44*a(n-11) +39*a(n-12) +3*a(n-13) -a(n-14) for n>15

Example

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

Crossrefs

Sequence in context: A208068 A207933 A207850 * A208687 A207351 A207773

Adjacent sequences: A208836 A208837 A208838 * A208840 A208841 A208842

Keyword

nonn

Author

R. H. Hardin Mar 01 2012

Status

approved