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A252213 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 5 6 or 7 1

%I

%S 1212,1078,1437,2836,6674,17478,47580,130032,357094,983466,2708592,

%T 7459998,20551442,56618848,155979808,429716464,1183857470,3261485984,

%U 8985277196,24754145982,68196861104,187880081284,517603412018

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

%C Column 2 of A252219

%H R. H. Hardin, <a href="/A252213/b252213.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +2*a(n-2) +9*a(n-3) +2*a(n-4) -5*a(n-5) -23*a(n-6) -14*a(n-7) +2*a(n-8) +25*a(n-9) +20*a(n-10) +4*a(n-11) -12*a(n-12) -11*a(n-13) -4*a(n-14) +2*a(n-15) +2*a(n-16) +a(n-17) for n>25

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 15 2014

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Last modified October 24 20:35 EDT 2021. Contains 348233 sequences. (Running on oeis4.)