A184000 - OEIS

%I #8 Apr 09 2018 14:45:49

%S 5175,6417,8415,12525,19935,35565,66591,134853,282735,628557,1444815,

%T 3494805,8731935,22771005,60933951,168205893,472111695,1351666797,

%U 3905565615,11418586485,33538635135,99183404445,293959431711

%N Number of (n+1) X 7 0..2 arrays with all 2 X 2 subblock sums the same.

%C Column 6 of A184003.

%H R. H. Hardin, <a href="/A184000/b184000.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 6*a(n-1) - 60*a(n-3) + 85*a(n-4) + 150*a(n-5) - 360*a(n-6) + 396*a(n-8) - 216*a(n-9).

%F Empirical g.f.: 3*x*(1725 - 8211*x - 10029*x^2 + 90845*x^3 - 36690*x^4 - 300280*x^5 + 263292*x^6 + 304884*x^7 - 328536*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - 6*x^2)). - _Colin Barker_, Apr 09 2018

%e Some solutions for 3 X 7:

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

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

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

%Y Cf. A184003.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 08 2011