A237574 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.

256, 1876, 1876, 13924, 24332, 13924, 103264, 315664, 315664, 103264, 769680, 4146324, 7379204, 4146324, 769680, 5705156, 54395184, 173478980, 173478980, 54395184, 5705156, 42501300, 712810024, 4093774632, 7415425124, 4093774632

Offset: 1

Author

R. H. Hardin, Feb 09 2014

Keywords

• nonn
• tabl

Comments

Table starts

.......256.........1876..........13924............103264...............769680

......1876........24332.........315664...........4146324.............54395184

.....13924.......315664........7379204.........173478980...........4093774632

....103264......4146324......173478980........7415425124.........313460630304

....769680.....54395184.....4093774632......313460630304.......23898935623162

...5705156....712810024....95639726868....13253873415032.....1807232491974520

..42501300...9341685548..2255748816966...561018557350096...138024943528283880

.315065200.122455823868.52746091216472.23744013911896432.10448941120238123892

Examples

			Some solutions for n=2 k=4
..0..0..0..1..1....0..0..1..1..3....0..0..1..0..0....0..0..1..2..0
..0..2..1..2..3....1..0..3..0..0....1..2..1..0..3....0..0..1..1..2
..3..3..2..0..2....0..1..1..2..0....2..3..3..1..0....3..1..2..3..2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..84

Formula

Empirical for column k:

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

k=2: [order 45]