A220328 - OEIS

%I #4 Dec 10 2012 18:13:37

%S 1,1,1,2,4,1,4,16,12,1,7,48,92,37,1,12,174,572,508,114,1,21,658,4062,

%T 6657,2788,351,1,37,2482,29467,92093,76627,15316,1081,1,65,9229,

%U 213225,1335202,2065264,876714,84196,3329,1,114,33982,1540686,18836493,59893608

%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 and antidiagonal neighbors in a random 0..1 nXk array

%C Table starts

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

%C .1.....4......16........48........174........658.......2482......9229

%C .1....12......92.......572.......4062......29467.....213225...1540686

%C .1....37.....508......6657......92093....1335202...18836493.265346645

%C .1...114....2788.....76627....2065264...59893608.1653121774

%C .1...351...15316....876714...46094354.2680626797

%C .1..1081...84196..10004541.1026529800

%C .1..3329..462940.114058230

%C .1.10252.2545492

%C .1.31572

%C .1

%H R. H. Hardin, <a href="/A220328/b220328.txt">Table of n, a(n) for n = 1..70</a>

%e Some solutions for n=3 k=4

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

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

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

%Y Column 2 is A099098

%Y Row 1 is A005251(n+1)

%K nonn,tabl

%O 1,4

%A _R. H. Hardin_ Dec 10 2012