A206890 - OEIS

%I #5 Mar 31 2012 12:37:14

%S 12,144,1112,7878,59812,467146,3619683,27856426,214439388,1653053388,

%T 12745491312,98247659290,757270935480,5837067310185,44993325501460,

%U 346816977981142,2673316454328453,20606310351329382,158836581856928905

%N Number of 4Xn 0..1 arrays avoiding 0 1 0 horizontally and 1 0 0 vertically

%C Row 4 of A206889

%H R. H. Hardin, <a href="/A206890/b206890.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 10*a(n-1) -45*a(n-2) +229*a(n-3) -218*a(n-4) +252*a(n-5) +4284*a(n-6) -13089*a(n-7) +3791*a(n-8) +11569*a(n-9) -213388*a(n-10) +260583*a(n-11) +666011*a(n-12) -920482*a(n-13) +2316886*a(n-14) +1153148*a(n-15) -19066932*a(n-16) -2877461*a(n-17) +45161671*a(n-18) +12663738*a(n-19) -32021544*a(n-20) -21458469*a(n-21) -43223410*a(n-22) +3294189*a(n-23) +77036208*a(n-24) +23573846*a(n-25) +2828063*a(n-26) -12109495*a(n-27) -59453958*a(n-28) -11713631*a(n-29) +8381537*a(n-30) +5628040*a(n-31) +26008202*a(n-32) +3592611*a(n-33) -1894784*a(n-34) -982584*a(n-35) -6505534*a(n-36) -624915*a(n-37) -435627*a(n-38) +65742*a(n-39) +750118*a(n-40) +52218*a(n-41) +125258*a(n-42) -3547*a(n-43) -31348*a(n-44) -2379*a(n-45) -6806*a(n-46) +95*a(n-47) +594*a(n-48) +36*a(n-49) +133*a(n-50) -6*a(n-52) -a(n-54)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 13 2012