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A220808 Equals one maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..2 nX4 array 1
8, 168, 3466, 62400, 1037774, 16734366, 268264812, 4294285044, 68716748256, 1099500713960, 17592142389240, 281474802089984, 4503598928887808, 72057591243997184, 1152921493431123968, 18446744029006659584 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A220810

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..33

FORMULA

Empirical: a(n) = 20*a(n-1) -64*a(n-2) for n>13

EXAMPLE

Some solutions for n=3

..0..1..0..0....0..0..1..1....0..0..1..1....0..1..1..0....1..0..1..1

..1..0..0..1....1..1..0..1....1..1..0..1....1..0..0..1....0..0..1..0

..0..0..0..0....0..0..0..0....0..0..1..0....1..1..0..0....0..0..0..0

CROSSREFS

Sequence in context: A316756 A294512 A090228 * A221022 A039699 A307347

Adjacent sequences:  A220805 A220806 A220807 * A220809 A220810 A220811

KEYWORD

nonn

AUTHOR

R. H. Hardin Dec 22 2012

STATUS

approved

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Last modified October 24 05:38 EDT 2021. Contains 348217 sequences. (Running on oeis4.)