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Number of (n+1) X (6+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally.
1

%I #10 Dec 15 2018 11:05:54

%S 1081504,15888,7784,8272,12680,12800,20864,36352,99200,108800,230144,

%T 485632,1483520,1644800,3578624,7674112,23632640,26220800,57154304,

%U 122689792,378018560,419436800,914365184,1962940672,6048193280

%N Number of (n+1) X (6+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally.

%H R. H. Hardin, <a href="/A253467/b253467.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-2) + 16*a(n-4) - 16*a(n-6) for n>8.

%F Empirical g.f.: 8*x*(135188 + 1986*x - 134215*x^2 - 952*x^3 - 2162396*x^4 - 31210*x^5 + 2148463*x^6 + 18176*x^7) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 + 4*x^2)). - _Colin Barker_, Dec 15 2018

%e Some solutions for n=1.

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

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

%Y Column 6 of A253468.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 01 2015