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A252303 Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7 1

%I

%S 7138,5056,6103,8130,15444,24076,33862,71636,117612,167798,385332,

%T 662964,951766,2359892,4219348,6078806,16019028,29452116,42525526,

%U 116755796,218457940,315839318,888530772,1679113044,2429346646,6926306132

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

%C Column 6 of A252305

%H R. H. Hardin, <a href="/A252303/b252303.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-3) -70*a(n-6) +120*a(n-9) -64*a(n-12) for n>21

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014

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Last modified July 3 11:43 EDT 2022. Contains 355050 sequences. (Running on oeis4.)