A240632 Number of nX4 0..1 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..1 introduced in row major order

8, 81, 637, 4989, 38634, 299329, 2319211, 17971509, 139264013, 1079178635, 8362717691, 64803934520, 502175240181, 3891429932618, 30155264060461, 233677585671980, 1810802052546549, 14032171994804298, 108737368953561194

Offset

1,1

Comments

Column 4 of A240636

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +7*a(n-2) -9*a(n-3) -3*a(n-4) +6*a(n-5) +11*a(n-6) +56*a(n-7) -211*a(n-8) -553*a(n-9) -266*a(n-10) +569*a(n-11) +514*a(n-12) +241*a(n-13) +672*a(n-14) +985*a(n-15) +518*a(n-16) +71*a(n-17) -161*a(n-18) -845*a(n-19) -670*a(n-20) -783*a(n-21) -620*a(n-22) -263*a(n-23) +134*a(n-24) +196*a(n-25) +238*a(n-26) +159*a(n-27) +70*a(n-28) +5*a(n-29) -14*a(n-30) -18*a(n-31) -8*a(n-32)

Example

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

Crossrefs

Sequence in context: A343274 A240480 A274752 * A007792 A301837 A264185

Adjacent sequences: A240629 A240630 A240631 * A240633 A240634 A240635

Keyword

nonn

Author

R. H. Hardin, Apr 09 2014

Status

approved