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 A252249 Number of (n+2) X (3+2) 0..3 arrays with every 3 X 3 subblock row and column sum not equal to 0 3 5 6 or 7 and every 3 X 3 diagonal and antidiagonal sum equal to 0 3 5 6 or 7. 1

%I

%S 278,242,231,249,279,318,366,444,546,672,876,1143,1473,2007,2706,3570,

%T 4968,6798,9060,12720,17511,23433,33015,45558,61062,86148,118986,

%U 159576,225252,311223,417489,589431,814506,1092714,1542864,2132118,2860476

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

%H R. H. Hardin, <a href="/A252249/b252249.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 3*a(n-3) - 3*a(n-4) - a(n-6) + a(n-7) for n>9.

%F Empirical g.f.: x*(278 - 36*x - 11*x^2 - 816*x^3 + 138*x^4 + 72*x^5 + 272*x^6 - 48*x^7 - 26*x^8) / ((1 - x)*(1 - 3*x^3 + x^6)). - _Colin Barker_, Dec 02 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 3 of A252254.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014

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Last modified January 16 18:07 EST 2022. Contains 350376 sequences. (Running on oeis4.)