login
Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it, modulo 4
1

%I #4 Mar 27 2014 09:05:16

%S 4,23,113,582,2981,15266,78188,400542,2051667,10509067,53831920,

%T 275740995,1412438656,7234951864,37059718148,189831642853,

%U 972377820507,4980827553280,25513377870835,130687610786192,669423377137934

%N Number of nX2 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of elements above it, modulo 4

%C Column 2 of A239819

%H R. H. Hardin, <a href="/A239813/b239813.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +16*a(n-2) +31*a(n-3) -8*a(n-4) -78*a(n-5) -45*a(n-6) +56*a(n-7) -32*a(n-8) +32*a(n-9) +16*a(n-10)

%e Some solutions for n=5

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 27 2014