A239405 T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it, modulo 4.

2, 4, 5, 8, 23, 12, 16, 105, 129, 28, 32, 478, 1337, 698, 66, 64, 2165, 13977, 16449, 3805, 156, 128, 9811, 144762, 394509, 205969, 20818, 368, 256, 44399, 1504399, 9340070, 11334364, 2590704, 113774, 868, 512, 201006, 15591122, 222457036, 614216271

Offset: 1

Author

R. H. Hardin, Mar 17 2014

Keywords

• nonn
• tabl

Comments

Table starts

....2.......4..........8............16................32...................64

....5......23........105...........478..............2165.................9811

...12.....129.......1337.........13977............144762..............1504399

...28.....698......16449........394509...........9340070............222457036

...66....3805.....205969......11334364.........614216271..........33522573911

..156...20818....2590704.....326882784.......40566958960........5072216819342

..368..113774...32507376....9402398952.....2671846338458......765206237815409

..868..621754..408000104..270516990628...176044655676921...115478426410506313

.2048.3399032.5124790809.7789048968124.11610439554314901.17442858177037612521

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..180

Crossrefs

Column 1 is A239333

Row 1 is A000079

Formula

Empirical for column k:

k=1: a(n) = 2*a(n-1) +2*a(n-3)

k=2: [order 16]

k=3: [order 64]

Empirical for row n:

n=1: a(n) = 2*a(n-1)

n=2: a(n) = 3*a(n-1) +12*a(n-2) -18*a(n-3) -29*a(n-4) +19*a(n-5) +38*a(n-6) +8*a(n-7)

n=3: [order 25]

n=4: [order 91]