A212478 - OEIS

%I #4 May 17 2012 14:41:44

%S 5864,172980,3708268,70600212,1246724695,21292987433,357117150362,

%T 5923063781205,97514964737576,1597131825489558,26058934302628094,

%U 423954039651724411,6881835973423757103,111509561797692820078

%N Number of 0..3 arrays of length 2*n+6 with sum no more than 3*n in any length 2n subsequence (=50% duty cycle)

%C Row 7 of A212471

%H R. H. Hardin, <a href="/A212478/b212478.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=3

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

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

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

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

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

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ May 17 2012