A252946 - OEIS

%I #4 Dec 25 2014 07:02:32

%S 747,2988,12915,57978,262494,1192149,5419521,24648309,112122162,

%T 510068277,2320483212,10556851032,48027819627,218500501500,

%U 994059717210,4522438970532,20574677747547,93603784061979,425847190478391

%N Number of (n+2)X(2+2) 0..2 arrays with every consecutive three elements in every row, column and nw-se diagonal having exactly two distinct values, and new values 0 upwards introduced in row major order

%C Column 2 of A252952

%H R. H. Hardin, <a href="/A252946/b252946.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -5*a(n-2) -8*a(n-3) +4*a(n-4) -7*a(n-5) +14*a(n-6) +19*a(n-7) -14*a(n-8) -12*a(n-9) -24*a(n-10) -47*a(n-11) +18*a(n-12) +31*a(n-13) +7*a(n-14) +40*a(n-15) -5*a(n-16) +a(n-17) -11*a(n-18) -12*a(n-19) +2*a(n-20) +5*a(n-21) -a(n-22)

%e Some solutions for n=4

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

%e ..0..1..1..0....2..2..0..0....1..1..0..0....0..2..0..2....1..2..1..1

%e ..1..1..0..0....2..1..2..1....1..0..0..1....2..0..0..1....0..1..0..0

%e ..1..2..1..1....1..2..2..0....0..0..1..0....2..2..1..2....0..1..0..0

%e ..2..1..1..0....1..1..0..1....1..1..0..0....1..0..0..1....1..2..1..1

%e ..1..2..2..1....0..2..2..0....1..0..0..1....2..0..0..2....0..1..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 25 2014