A210784 Number of nX4 1..4 arrays with no element with value z exactly a city block distance of z from another element with value z

170, 8824, 142627, 1115472, 8039420, 69751928, 890122678, 13542249784, 192792997988, 2360679608394, 26209216760706, 293049578829142, 3503962366035752, 44266390297992974, 561080274874096444

Offset

1,1

Comments

Column 4 of A210788

Links

R. H. Hardin, Table of n, a(n) for n = 1..132

Example

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

Crossrefs

Sequence in context: A031614 A289648 A187520 * A178499 A133328 A098244

Adjacent sequences: A210781 A210782 A210783 * A210785 A210786 A210787

Keyword

nonn

Author

R. H. Hardin Mar 26 2012

Status

approved