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A252528 Number of (n+2) X (4+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7. 1

%I #8 Dec 04 2018 11:03:58

%S 719,462,626,790,1676,2504,3160,6704,10016,12640,26816,40064,50560,

%T 107264,160256,202240,429056,641024,808960,1716224,2564096,3235840,

%U 6864896,10256384,12943360,27459584,41025536,51773440,109838336

%N Number of (n+2) X (4+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7.

%H R. H. Hardin, <a href="/A252528/b252528.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-3) for n>5.

%F Empirical g.f.: x*(719 + 462*x + 626*x^2 - 2086*x^3 - 172*x^4) / (1 - 4*x^3). - _Colin Barker_, Dec 04 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 4 of A252532.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014

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Last modified April 18 11:00 EDT 2024. Contains 371779 sequences. (Running on oeis4.)