A208365 Number of nX4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically

10, 100, 450, 1953, 9338, 41433, 177909, 774134, 3350020, 14367500, 61642245, 264469320, 1132543047, 4847303685, 20747148598, 88770363000, 379728672366, 1624285944365, 6947428890150, 29713533493473, 127078745348389

Offset

1,1

Comments

Column 4 of A208369

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -7*a(n-2) +61*a(n-3) -179*a(n-4) +58*a(n-5) -1068*a(n-6) +1917*a(n-7) +2026*a(n-8) +9988*a(n-9) -9428*a(n-10) -29734*a(n-11) -73148*a(n-12) +26874*a(n-13) +184416*a(n-14) +381506*a(n-15) +1583*a(n-16) -717754*a(n-17) -1330911*a(n-18) -304488*a(n-19) +1765519*a(n-20) +3232917*a(n-21) +1188725*a(n-22) -2826789*a(n-23) -5332371*a(n-24) -2626532*a(n-25) +2852216*a(n-26) +6004925*a(n-27) +3574946*a(n-28) -1517279*a(n-29) -4478716*a(n-30) -3200295*a(n-31) +161307*a(n-32) +2089368*a(n-33) +1784642*a(n-34) +294445*a(n-35) -587058*a(n-36) -585976*a(n-37) -123230*a(n-38) +116114*a(n-39) +125474*a(n-40) -1852*a(n-41) -48554*a(n-42) -34574*a(n-43) +625*a(n-44) +16564*a(n-45) +13467*a(n-46) +4682*a(n-47) -665*a(n-48) -1887*a(n-49) -1477*a(n-50) -427*a(n-51) -99*a(n-52) +76*a(n-53) +46*a(n-54) +9*a(n-55) +a(n-56) -2*a(n-57) -a(n-58)

Example

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

Crossrefs

Sequence in context: A207706 A207251 A208289 * A208144 A207713 A222716

Adjacent sequences: A208362 A208363 A208364 * A208366 A208367 A208368

Keyword

nonn

Author

R. H. Hardin Feb 25 2012

Status

approved