A219877 Number of n X n arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X n array.

3, 7, 47, 621, 14536, 764027, 113313853

Offset

1,1

Links

Table of n, a(n) for n=1..7.

Example

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

Crossrefs

Diagonal of A219883.

Sequence in context: A020754 A052381 A391053 * A031440 A331038 A001566

Adjacent sequences: A219874 A219875 A219876 * A219878 A219879 A219880

Keyword

nonn,more

Author

R. H. Hardin, Nov 30 2012

Status

approved