A236664 - OEIS

%I #9 Oct 21 2018 13:44:47

%S 81,452,2608,14760,84948,484400,2771648,15802528,90361616,516384576,

%T 2952092672,16860669056,96327668544,550413844224,3145705321472,

%U 17974353615360,102695841511680,586762124067840,3352875664056320

%N Number of (n+1) X (1+1) 0..2 arrays colored with the maximum plus the lower median minus the upper median minus the minimum of every 2 X 2 subblock.

%H R. H. Hardin, <a href="/A236664/b236664.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + 436*a(n-4) + 888*a(n-5) + 2304*a(n-6) + 5760*a(n-7).

%F Empirical g.f.: x*(81 + 290*x + 1704*x^2 + 9544*x^3 + 20112*x^4 + 45504*x^5 + 77760*x^6) / (1 - 2*x - 436*x^4 - 888*x^5 - 2304*x^6 - 5760*x^7). - _Colin Barker_, Oct 21 2018

%e Some solutions for n=5:

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

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

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

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

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

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

%Y Column 1 of A236669.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 29 2014