%I #6 Apr 23 2021 11:38:51
%S 793,11518,131950,1376128,13468524,128148456,1200645159,11143104246,
%T 102770036310,943639250739,8636456931969,78848824010001,
%U 718489851092745,6537040547889223,59402114237433426,539234176052230974
%N Number of 0..2 arrays of length 6+2*n with sum no more than 2*n in any length 2n subsequence (=50% duty cycle).
%C Row 7 of A212232.
%H R. H. Hardin, <a href="/A212239/b212239.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..1....0....2....1....1....1....0....0....1....0....1....0....0....1....1....1
%e ..0....1....0....0....0....2....0....2....1....0....1....0....0....1....0....2
%e ..2....1....0....0....2....0....0....2....0....0....0....2....1....2....0....0
%e ..0....0....0....0....1....2....1....0....0....1....1....1....2....0....0....2
%e ..1....0....0....0....1....1....2....1....1....0....2....2....1....2....1....0
%e ..1....1....0....0....1....0....1....0....0....2....0....1....0....0....0....1
%e ..2....0....0....0....0....1....0....0....0....0....0....0....0....0....0....0
%e ..0....0....0....0....1....0....0....2....2....0....2....0....0....0....1....1
%e ..1....0....1....2....1....0....2....0....0....0....0....2....0....1....0....1
%e ..0....1....0....0....1....1....1....0....0....2....1....0....0....1....2....1
%e ..0....1....1....2....1....0....1....2....0....1....1....1....2....1....1....2
%e ..0....0....1....1....0....2....1....0....1....0....1....2....0....0....2....0
%Y Cf. A212232.
%K nonn
%O 1,1
%A _R. H. Hardin_ May 06 2012