**G.f.: (x+2)*(x+1)/((x-1)*(x-2)) = Sum(n=0,inf,a(n)*(x/2)^n).**

*1, 3, 9, 21, 45, 93, 189, 381, 765, 1533, 3069, 6141, 12285, 24573, 49149, 98301*

*1 seqfan posts*

Index of A-numbers in seqfan: by ascending order by month by frequency by keyword

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