A221331 - OEIS

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A221331

Number of 4Xn arrays of occupancy after each element stays put or moves to some horizontal or antidiagonal neighbor, with no occupancy greater than 2

1, 577, 33873, 2460824, 162430981, 10794156688, 711858713069, 46910596287335, 3089778765626866, 203426990390736036, 13389504827335440162, 881130781309712234876, 57978558022828544235124, 3814742757245230038689495

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Row 4 of A221328

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..27

EXAMPLE

Some solutions for n=3

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

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

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