A220406 - OEIS

%I #4 Dec 13 2012 17:42:58

%S 1,1,1,2,6,1,4,17,23,1,7,40,122,78,1,12,93,908,720,292,1,21,206,6013,

%T 10989,4304,1066,1,37,431,41510,128448,139233,25391,3922,1,65,924,

%U 273253,1701214,2996186,1782679,150079,14420,1,114,1863,1851686,20736643

%N T(n,k)=Equals two maps: number of nXk binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal, diagonal and antidiagonal neighbors in a random 0..1 nXk array

%C Table starts

%C .1.....1......2........4........7.......12.......21........37.......65..114.200

%C .1.....6.....17.......40.......93......206......431.......924.....1863.3898

%C .1....23....122......908.....6013....41510...273253...1851686.12276677

%C .1....78....720....10989...128448..1701214.20736643.263993960

%C .1...292...4304...139233..2996186.76047436

%C .1..1066..25391..1782679.74035199

%C .1..3922.150079.22578152

%C .1.14420.884793

%C .1.53082

%C .1

%H R. H. Hardin, <a href="/A220406/b220406.txt">Table of n, a(n) for n = 1..59</a>

%e Some solutions for n=3 k=4

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

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

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

%Y Column 2 is A220238

%Y Row 1 is A005251(n+1)

%K nonn,tabl

%O 1,4

%A _R. H. Hardin_ Dec 13 2012