A222833 - OEIS

A222833

Number of n X n 0..3 arrays with no element equal to another at a city block distance of exactly two, and new values 0..3 introduced in row major order

1, 7, 72, 600, 4032, 24576, 138240, 743424, 3833856, 19267584, 94371840, 454557696

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OFFSET

1,2

COMMENTS

Diagonal of A222838

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

Some solutions for n=4

..0..1..1..2....0..1..1..0....0..1..2..2....0..1..2..0....0..1..2..3

..3..2..0..0....0..2..3..3....2..3..3..0....0..3..3..0....3..1..2..3

..1..2..3..1....1..2..0..1....2..0..1..1....2..2..1..1....2..0..0..1

..0..0..3..1....1..3..0..1....1..0..2..2....3..0..0..2....2..3..3..2

CROSSREFS

Sequence in context: A093632 A242827 A077332 * A005413 A306377 A230890

Adjacent sequences: A222830 A222831 A222832 * A222834 A222835 A222836

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 06 2013

STATUS

approved