%I #4 Nov 03 2012 13:41:37

%S 1,13,57,225,895,3565,14189,56489,224891,895325,3564433,14190565,

%T 56494859,224914869,895421261,3564812065,14192074291,56500867089,

%U 224938787413,895516488309,3565191179595,14193583605661,56506875907213

%N 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

%C Row 2 of A218592

%H R. H. Hardin, <a href="/A218593/b218593.txt">Table of n, a(n) for n = 1..210</a>

%F 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

%e Some solutions for n=3

%e ..0..0..0....0..0..0....1..0..0....0..0..1....1..0..0....0..1..0....1..0..1

%e ..1..1..1....1..0..1....0..1..0....0..0..1....1..1..1....1..1..1....1..1..1

%K nonn

%O 1,2

%A _R. H. Hardin_ Nov 03 2012