A239357 Number of n X n 0..2 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 3.

2, 7, 17, 43, 106, 266, 729, 2151, 7018, 24408, 89336, 357201, 1458929, 5961455, 24784580, 107143015, 480468133, 2242277805, 11003117564

Offset

1,1

Comments

Diagonal of A239361

Links

Table of n, a(n) for n=1..19.

Example

Some solutions for n=5
..0..0..0..0..0....0..0..0..0..2....0..0..0..0..0....2..2..0..0..0
..0..0..0..0..0....0..0..0..2..2....0..0..0..0..0....2..1..2..2..0
..0..0..0..2..2....0..0..0..2..1....0..0..0..0..0....0..2..2..1..2
..0..0..0..2..2....0..0..0..0..2....0..0..0..0..0....0..2..1..2..2
..0..2..2..0..1....2..2..0..0..0....0..0..0..2..2....0..0..2..1..0

Crossrefs

Sequence in context: A375821 A175120 A393177 * A106910 A108479 A178441

Adjacent sequences: A239354 A239355 A239356 * A239358 A239359 A239360

Keyword

nonn

Author

R. H. Hardin, Mar 17 2014

Status

approved