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A219074
Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, diagonal or antidiagonal neighbor in a random 0..1 nX4 array
1
9, 165, 2321, 32945, 477309, 6879341, 99118753, 1428782305, 20594013941, 296830835781, 4278398369137, 61667023808785, 888841954030797, 12811387949686973, 184657868037699425, 2661579521073401057
OFFSET
1,1
COMMENTS
Column 4 of A219078
LINKS
FORMULA
Empirical: a(n) = 11*a(n-1) +33*a(n-2) +233*a(n-3) +13*a(n-4) -31*a(n-5) -657*a(n-6) -321*a(n-7) -288*a(n-8) -64*a(n-9) +64*a(n-10)
EXAMPLE
Some solutions for n=3
..1..1..0..1....0..1..0..0....1..1..0..0....0..0..1..1....1..1..1..0
..1..1..1..1....0..1..1..1....1..1..1..1....0..1..1..0....0..0..1..1
..0..0..1..1....0..0..1..0....1..0..0..0....1..0..1..1....1..1..1..0
CROSSREFS
Sequence in context: A377329 A086759 A053130 * A166180 A376174 A004107
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 11 2012
STATUS
approved