A203819 Number of (n+1)X2 0..3 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements

144, 1296, 11664, 104976, 944784, 8503056, 76527504, 688747536, 6198727824, 55788550416, 502096953744, 4518872583696, 40669853253264, 366028679279376, 3294258113514384, 29648323021629456, 266834907194665104

Offset

1,1

Comments

Column 1 of A203826

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 16*9^n

Example

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

Crossrefs

Sequence in context: A211473 A203826 A261655 * A222515 A023096 A223435

Adjacent sequences: A203816 A203817 A203818 * A203820 A203821 A203822

Keyword

nonn

Author

R. H. Hardin Jan 06 2012

Status

approved