A263218 - OEIS

%I #4 Oct 12 2015 11:45:24

%S 2,14,72,343,1920,11444,68112,405019,2422502,14527358,87130296,

%T 522558079,3134839248,18808467356,112848487824,677075548723,

%U 4062417593558,24374464952438,146246626666296,877478675492551,5264869525163232

%N Number of (n+1)X(2+1) 0..2 arrays with each row and column divisible by 5, read as a base-3 number with top and left being the most significant digits.

%C Column 2 of A263224.

%H R. H. Hardin, <a href="/A263218/b263218.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 8*a(n-1) -16*a(n-2) +32*a(n-3) +35*a(n-4) -664*a(n-5) +1328*a(n-6) -2656*a(n-7) +3121*a(n-8) +6904*a(n-9) -13808*a(n-10) +27616*a(n-11) -40643*a(n-12) -6248*a(n-13) +12496*a(n-14) -24992*a(n-15) +37488*a(n-16)

%e Some solutions for n=4

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

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

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

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

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

%Y Cf. A263224.

%K nonn

%O 1,1

%A _R. H. Hardin_, Oct 12 2015