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Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7
1

%I #4 Dec 10 2014 09:14:49

%S 1038,2146,3092,5756,11008,18400,32372,60292,100612,176372,322532,

%T 547244,957412,1726428,2976676,5237036,9377508,16323580,28791476,

%U 51347308,90018580,159196860,283147012,498087484,881978324,1566542540,2762581684

%N Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7

%C Column 1 of A251876

%H R. H. Hardin, <a href="/A251869/b251869.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 11*a(n-3) +6*a(n-5) -38*a(n-6) -58*a(n-8) +18*a(n-9) +208*a(n-11) +160*a(n-12) -328*a(n-14) -328*a(n-15) +192*a(n-17) +192*a(n-18) for n>23

%e Some solutions for n=4

%e ..0..1..0....3..3..2....3..1..2....0..2..1....3..1..2....1..0..2....0..1..0

%e ..1..2..0....3..3..0....0..2..1....1..2..0....0..0..3....0..3..0....0..2..1

%e ..0..3..0....0..2..1....3..3..0....2..2..2....3..2..1....2..3..1....0..0..0

%e ..2..1..0....0..3..0....0..1..2....3..2..1....0..1..2....1..0..2....3..1..2

%e ..1..2..3....1..3..2....3..2..1....3..2..3....0..3..3....3..0..0....3..2..1

%e ..0..3..0....2..3..1....0..3..0....2..2..2....0..2..1....2..0..1....3..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 10 2014