A206378 - OEIS

%I #5 Mar 31 2012 12:37:11

%S 641,25945,1198601,57656713,2808967145,137393517193,6728546532521,

%T 329641979105737,16151593118685929,791414923478310409,

%U 38779131391953424169,1900174398169760171593,93108499268211138032489

%N Number of (n+1)X4 0..3 arrays with every 2X2 subblock having the same number of equal diagonal or antidiagonal elements, and new values 0..3 introduced in row major order

%C Column 3 of A206383

%H R. H. Hardin, <a href="/A206378/b206378.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 74*a(n-1) -1401*a(n-2) +9064*a(n-3) -21992*a(n-4) +21312*a(n-5) -7056*a(n-6)

%e Some solutions for n=4

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

%e ..2..3..3..1....0..1..0..1....0..2..0..1....2..1..3..2....0..1..0..0

%e ..0..0..2..0....1..2..1..2....1..0..3..0....0..1..3..1....2..0..0..3

%e ..2..1..1..3....3..1..1..1....3..1..0..0....3..1..0..0....1..2..0..0

%e ..2..3..2..2....0..3..1..3....2..3..1..0....3..1..2..3....0..1..2..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 07 2012