A207124 - OEIS

%I #5 Mar 31 2012 12:37:15

%S 9,81,289,1024,4096,14161,45796,150544,481636,1493284,4601025,

%T 14055001,42380100,126900225,378108025,1119906225,3301766521,

%U 9702250000,28419216400,83012558161,241951836996,703860593296,2044150748644

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

%C Row 4 of A207123

%H R. H. Hardin, <a href="/A207124/b207124.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -12*a(n-2) +30*a(n-3) -105*a(n-4) +140*a(n-5) -191*a(n-6) +637*a(n-7) -525*a(n-8) +374*a(n-9) -2132*a(n-10) +851*a(n-11) -82*a(n-12) +4997*a(n-13) -364*a(n-14) -761*a(n-15) -7828*a(n-16) -1358*a(n-17) +1552*a(n-18) +7812*a(n-19) +2336*a(n-20) -1168*a(n-21) -4944*a(n-22) -1472*a(n-23) +512*a(n-24) +1632*a(n-25) +448*a(n-26) -128*a(n-27) -256*a(n-28)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 15 2012