A237574 - OEIS

%I #4 Feb 09 2014 07:07:15

%S 256,1876,1876,13924,24332,13924,103264,315664,315664,103264,769680,

%T 4146324,7379204,4146324,769680,5705156,54395184,173478980,173478980,

%U 54395184,5705156,42501300,712810024,4093774632,7415425124,4093774632

%N T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with the upper median minus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one

%C Table starts

%C .......256.........1876..........13924............103264...............769680

%C ......1876........24332.........315664...........4146324.............54395184

%C .....13924.......315664........7379204.........173478980...........4093774632

%C ....103264......4146324......173478980........7415425124.........313460630304

%C ....769680.....54395184.....4093774632......313460630304.......23898935623162

%C ...5705156....712810024....95639726868....13253873415032.....1807232491974520

%C ..42501300...9341685548..2255748816966...561018557350096...138024943528283880

%C .315065200.122455823868.52746091216472.23744013911896432.10448941120238123892

%H R. H. Hardin, <a href="/A237574/b237574.txt">Table of n, a(n) for n = 1..84</a>

%F Empirical for column k:

%F k=1: [linear recurrence of order 14] for n>15

%F k=2: [order 45]

%e Some solutions for n=2 k=4

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

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

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

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_, Feb 09 2014