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%I #10 Aug 10 2015 23:35:02
%S 966,1870,3886,8686,20490,50570,129378,340782,918878,2525262,7049658,
%T 19942026,57058610,164910430,480976574,1414571198,4192696714,
%U 12517386890,37626434786,113828691374,346430157502,1060262602062,3261932440186
%N Number of (n+1) X (4+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.
%C Column 4 of A251236.
%H R. H. Hardin, <a href="/A251232/b251232.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 13*a(n-1) -63*a(n-2) +122*a(n-3) +13*a(n-4) -371*a(n-5) +317*a(n-6) +308*a(n-7) -370*a(n-8) -144*a(n-9) +128*a(n-10) +48*a(n-11).
%e Some solutions for n=4:
%e ..0..2..0..3..0....1..1..0..2..2....3..1..3..1..1....0..1..0..1..1
%e ..1..3..1..2..1....2..2..3..1..1....0..2..0..2..2....2..3..2..3..1
%e ..2..0..2..1..2....1..1..0..2..2....3..1..3..1..1....0..1..0..1..1
%e ..3..1..3..0..3....1..3..2..2..0....1..1..1..1..3....2..3..2..3..1
%e ..1..1..1..2..1....2..0..1..1..3....3..1..3..1..1....1..0..1..0..2
%Y Cf. A251236.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 30 2014
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