cp's OEIS Frontend

A268420 Number of nX2 0..3 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.

%I A268420 #4 Feb 04 2016 09:51:17
%S A268420 2,15,187,2530,34195,448667,5720450,71224847,869969995,10461568690,
%T A268420 124193817155,1458609678443,16976365857602,196066210076847,
%U A268420 2249518678962747,25662410911209090,291308117338854611
%N A268420 Number of nX2 0..3 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order.
%C A268420 Column 2 of A268423.
%H A268420 R. H. Hardin, <a href="/A268420/b268420.txt">Table of n, a(n) for n = 1..210</a>
%F A268420 Empirical: a(n) = 33*a(n-1) -389*a(n-2) +1865*a(n-3) -2461*a(n-4) -3639*a(n-5) +7361*a(n-6) +2407*a(n-7) -5491*a(n-8) -585*a(n-9) +981*a(n-10) -81*a(n-11)
%e A268420 Some solutions for n=5
%e A268420 ..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..0....0..1....0..1
%e A268420 ..0..2....1..0....2..3....2..0....2..0....1..2....2..1....1..2....2..2....2..0
%e A268420 ..2..1....2..2....2..0....3..3....2..2....1..1....3..1....0..2....3..2....0..0
%e A268420 ..1..2....2..2....3..0....3..3....0..0....2..2....2..1....3..1....1..0....1..3
%e A268420 ..3..2....0..0....2..3....2..1....3..2....0..0....0..3....0..0....0..2....3..1
%Y A268420 Cf. A268423.
%K A268420 nonn
%O A268420 1,1
%A A268420 _R. H. Hardin_, Feb 04 2016