A208365 - OEIS

%I #5 Mar 31 2012 12:37:22

%S 10,100,450,1953,9338,41433,177909,774134,3350020,14367500,61642245,

%T 264469320,1132543047,4847303685,20747148598,88770363000,379728672366,

%U 1624285944365,6947428890150,29713533493473,127078745348389

%N Number of nX4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically

%C Column 4 of A208369

%H R. H. Hardin, <a href="/A208365/b208365.txt">Table of n, a(n) for n = 1..210</a>

%F 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)

%e Some solutions for n=4

%e ..1..1..0..1....0..1..1..0....0..1..0..1....1..1..1..1....0..1..1..0

%e ..1..0..1..1....1..1..0..0....0..1..0..0....1..0..1..0....1..0..1..0

%e ..0..1..1..0....1..1..0..0....0..1..0..1....1..1..1..1....1..1..0..0

%e ..0..1..1..1....0..1..0..0....0..1..0..1....0..1..0..1....1..1..1..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 25 2012