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%I #22 May 01 2019 17:32:23
%S 0,0,0,0,0,0,2,6,24,62,178,426,1070,2444,5720,12662,28392,61464,
%T 133980,285304,609750,1282278,2701396,5626046,11725614,24234418,
%U 50093914,102905764,211350724,432051438,882876204,1797686520
%N Number of 5-unbalanced strings of length n (=2^n-A027560(n)).
%C a(n) is also the number of different ways to fold down a folding yardstick with n sticks (stick length is one) to form an equilateral hexagon with side length one. - _Frank Hollstein_, May 01 2019
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (3,3,-14,2,15,-6).
%F G.f.: 2x^6/[(1-2x)(1-3x^2)(1-x-2x^2+x^3)].
%Y Cf. A027560.
%K nonn
%O 0,7
%A _R. K. Guy_, _David Callan_