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A252072 Number of (n+2)X(5+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4.

%I A252072 #6 Jun 02 2025 10:45:41
%S A252072 767,3029,17455,92225,480464,2547765,13460641,71027923,375675345,
%T A252072 1985308056,10482759501,55378851635,292644335776,1546162330278,
%U A252072 8168095347950,43152835319630,227991513370743,1204546728063178
%N A252072 Number of (n+2)X(5+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4.
%C A252072 Column 5 of A252075
%H A252072 R. H. Hardin, <a href="/A252072/b252072.txt">Table of n, a(n) for n = 1..210</a>
%F A252072 Empirical: a(n) = 2*a(n-1) +2*a(n-2) +39*a(n-3) +181*a(n-4) +262*a(n-5) +238*a(n-6) -1529*a(n-7) -4996*a(n-8) -1940*a(n-9) +5551*a(n-10) +17305*a(n-11) +23836*a(n-12) -26075*a(n-13) -64360*a(n-14) -11102*a(n-15) +51639*a(n-16) +81824*a(n-17) +35975*a(n-18) -53399*a(n-19) -80282*a(n-20) -59920*a(n-21) -23443*a(n-22) +72246*a(n-23) +40762*a(n-24) -1573*a(n-25) +23887*a(n-26) -59858*a(n-27) +34106*a(n-28) -6361*a(n-29) -81*a(n-30) +24130*a(n-31) -31441*a(n-32) +25513*a(n-33) -20671*a(n-34) +14968*a(n-35) -8162*a(n-36) +4626*a(n-37) -2679*a(n-38) +1036*a(n-39) -411*a(n-40) +180*a(n-41) -13*a(n-42) -16*a(n-43) +5*a(n-44) for n>46
%e A252072 Some solutions for n=4
%e A252072 ..2..2..2..1..2..2..2....2..2..2..2..1..2..2....2..2..2..2..2..2..1
%e A252072 ..2..1..2..2..2..1..2....2..1..2..2..2..2..2....1..2..2..2..1..2..2
%e A252072 ..2..2..2..2..2..2..2....2..2..2..2..2..1..2....2..2..2..2..2..2..2
%e A252072 ..2..2..1..2..2..2..1....2..2..1..2..2..2..2....2..2..2..2..2..2..2
%e A252072 ..2..2..2..2..2..2..2....1..2..2..2..2..2..1....1..2..2..2..2..2..1
%e A252072 ..2..2..2..1..2..2..2....2..1..2..2..2..2..2....2..1..2..2..2..2..2
%K A252072 nonn
%O A252072 1,1
%A A252072 _R. H. Hardin_, Dec 13 2014