A210786 Number of nX6 1..4 arrays with no element with value z exactly a city block distance of z from another element with value z

1407, 167910, 3846906, 69751928, 1663213556, 51104966068, 1928958791380, 72641549339434, 2458594514534208

Offset

1,1

Comments

Column 6 of A210788

Links

Table of n, a(n) for n=1..9.

Example

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

Crossrefs

Sequence in context: A158764 A035863 A045127 * A187957 A235906 A364184

Adjacent sequences: A210783 A210784 A210785 * A210787 A210788 A210789

Keyword

nonn

Author

R. H. Hardin Mar 26 2012

Status

approved