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A218593
Hilltop maps: number of 2Xn binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..2 2Xn array
1
1, 13, 57, 225, 895, 3565, 14189, 56489, 224891, 895325, 3564433, 14190565, 56494859, 224914869, 895421261, 3564812065, 14192074291, 56500867089, 224938787413, 895516488309, 3565191179595, 14193583605661, 56506875907213
OFFSET
1,2
COMMENTS
Row 2 of A218592
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) +3*a(n-2) +3*a(n-3) +a(n-4) +5*a(n-5) +2*a(n-6) +2*a(n-7) +a(n-8) +a(n-9) -a(n-10) -a(n-11) -a(n-12) -a(n-13) for n>14
EXAMPLE
Some solutions for n=3
..0..0..0....0..0..0....1..0..0....0..0..1....1..0..0....0..1..0....1..0..1
..1..1..1....1..0..1....0..1..0....0..0..1....1..1..1....1..1..1....1..1..1
CROSSREFS
Sequence in context: A007202 A368813 A222161 * A358303 A212405 A147384
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2012
STATUS
approved