%I #4 Nov 01 2013 18:11:39
%S 42,146,1682,6896,98296,396950,5528862,22368688,312355848,1263445694,
%T 17637095990,71342555920,995946010982,4028614953140,56239394873464,
%U 227489242462866,3175747801820816,12845949410201834,179329323720766570
%N Number of black-square subarrays of (n+2)X(5+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
%C Column 5 of A230935
%H R. H. Hardin, <a href="/A230932/b230932.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 63*a(n-2) -257*a(n-4) -6639*a(n-6) +14476*a(n-8) +210885*a(n-10) +297473*a(n-12) -149746*a(n-14) +3509820*a(n-16) +15998822*a(n-18) +18439507*a(n-20) -5600207*a(n-22) -23359537*a(n-24) -11139145*a(n-26) +4160133*a(n-28) +3040715*a(n-30) -1579065*a(n-32) -872680*a(n-34) +360423*a(n-36) +62740*a(n-38) -14788*a(n-40) +16*a(n-42) -256*a(n-44)
%e Some solutions for n=4
%e ..x..0..x..2..x..2..x....x..0..x..0..x..0..x....x..0..x..2..x..0..x
%e ..1..x..3..x..1..x..3....1..x..1..x..1..x..1....1..x..3..x..1..x..3
%e ..x..2..x..0..x..0..x....x..2..x..2..x..2..x....x..2..x..0..x..0..x
%e ..1..x..1..x..1..x..3....1..x..3..x..1..x..3....1..x..3..x..3..x..1
%e ..x..0..x..2..x..0..x....x..0..x..2..x..0..x....x..2..x..2..x..2..x
%e ..3..x..1..x..3..x..3....3..x..3..x..1..x..3....1..x..1..x..1..x..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 01 2013