A207309 - OEIS

%I #5 Mar 31 2012 12:37:16

%S 12,144,556,2239,7093,23091,79802,271023,906448,3057442,10340359,

%T 34870751,117557963,396686326,1338456663,4514922232,15230949488,

%U 51384415639,173349069871,584798251431,1972858125612,6655586739783

%N Number of 6Xn 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 1 0 vertically

%C Row 6 of A207305

%H R. H. Hardin, <a href="/A207309/b207309.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +3*a(n-2) +13*a(n-3) +18*a(n-4) -2*a(n-5) -30*a(n-6) -59*a(n-7) -25*a(n-8) +16*a(n-9) +68*a(n-10) +44*a(n-11) +3*a(n-12) -42*a(n-13) -23*a(n-14) -3*a(n-15) +17*a(n-16) +a(n-17) -2*a(n-18) -2*a(n-19) +3*a(n-20) -a(n-21) for n>22

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 16 2012