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%I #8 Oct 20 2019 17:48:17
%S 0,0,1,3,6,13,25,45,91,175,322,645,1245,2325,4651,9031,17061,34123,
%T 66547,126763,253527,496063,950818,1901637,3730293,7184421,14368843,
%U 28243063,54604081,109208163,215008363,416990563,833981127
%N Duplicate of A047194.
%K dead
%O 1,4