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A252673 Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 5 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 5 6 or 7 1

%I

%S 775,630,991,1677,3573,7164,13494,30552,63153,121564,279871,585918,

%T 1135346,2626993,5528908,10742509,24904376,52533179,102187158,

%U 237103008,500642761,974327011,2261578642,4777472917,9299731171,21589972325

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

%C Column 2 of A252679

%H R. H. Hardin, <a href="/A252673/b252673.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 22*a(n-3) -178*a(n-6) +713*a(n-9) -1673*a(n-12) +2744*a(n-15) -3188*a(n-18) +2096*a(n-21) -668*a(n-24) +103*a(n-27) +38*a(n-30) -8*a(n-33) for n>37

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 20 2014

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Last modified June 15 12:29 EDT 2021. Contains 345048 sequences. (Running on oeis4.)