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A252421 Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7 1

%I

%S 3719,7186,30724,62288,365974,1757580,3582225,21882869,107926383,

%T 220463165,1375056342,6880842955,14073466867,88795680194,447871169161,

%U 916696939171,5820110209906,29480626550553,60364093961967

%N Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7

%C Column 6 of A252423

%H R. H. Hardin, <a href="/A252421/b252421.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 135*a(n-3) -6200*a(n-6) +129658*a(n-9) -1479172*a(n-12) +10122008*a(n-15) -43818900*a(n-18) +123860492*a(n-21) -233367460*a(n-24) +297742037*a(n-27) -261058827*a(n-30) +159867108*a(n-33) -69122310*a(n-36) +20695032*a(n-39) -3955984*a(n-42) +409280*a(n-45) -16896*a(n-48) for n>56

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 2014

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Last modified February 1 19:27 EST 2023. Contains 359995 sequences. (Running on oeis4.)