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%I #4 Nov 01 2013 20:16:49
%S 76,724,8374,85196,854206,8838040,91616256,944382122,9735444252,
%T 100434191824,1036029240624,10686275566528,110228673309452,
%U 1137013355879738,11728259371943234,120976628016491406
%N Number of (n+3)X(3+3) 0..3 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, and upper left element zero
%C Column 3 of A230949
%H R. H. Hardin, <a href="/A230944/b230944.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 11*a(n-1) -23*a(n-2) +150*a(n-3) +309*a(n-4) -2148*a(n-5) +10102*a(n-6) -47494*a(n-7) -27771*a(n-8) -127963*a(n-9) -856209*a(n-10) -751900*a(n-11) +518927*a(n-12) +1522290*a(n-13) +5226896*a(n-14) +6396332*a(n-15) -6910959*a(n-16) -15629371*a(n-17) +577087*a(n-18) +12661958*a(n-19) +107867*a(n-20) -3633560*a(n-21) +898870*a(n-22) +447610*a(n-23) -220949*a(n-24) -31637*a(n-25) -855*a(n-26) +2592*a(n-27) +865*a(n-28) +42*a(n-29) +4*a(n-30)
%e Some solutions for n=2
%e ..0..x..0..x..1..x....0..x..2..x..2..x....0..x..0..x..3..x....0..x..2..x..2..x
%e ..x..1..x..1..x..2....x..1..x..3..x..1....x..1..x..0..x..2....x..1..x..3..x..1
%e ..0..x..2..x..3..x....2..x..0..x..1..x....2..x..0..x..1..x....0..x..0..x..2..x
%e ..x..3..x..2..x..0....x..3..x..0..x..2....x..3..x..3..x..0....x..1..x..3..x..1
%e ..2..x..1..x..1..x....2..x..2..x..3..x....2..x..2..x..2..x....0..x..2..x..0..x
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 01 2013