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A252529 Number of (n+2) X (5+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 11:04:04

%S 778,706,1120,1592,4420,7136,10720,30752,49792,77696,227584,369152,

%T 589312,1746944,2836480,4585472,13680640,22224896,36167680,108265472,

%U 175931392,287277056,861405184,1399980032,2289958912,6872367104

%N Number of (n+2) X (5+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="/A252529/b252529.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 12*a(n-3) - 32*a(n-6) for n>8.

%F Empirical g.f.: 2*x*(389 + 353*x + 560*x^2 - 3872*x^3 - 2026*x^4 - 3152*x^5 + 8256*x^6 + 152*x^7) / ((1 - 2*x)*(1 + 2*x + 4*x^2)*(1 - 4*x^3)). - _Colin Barker_, Dec 04 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 5 of A252532.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014

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Last modified April 24 07:05 EDT 2024. Contains 371920 sequences. (Running on oeis4.)