**G.f.: x^3/(1-2*x+x^3-x^4). Recurrence: a(n) = 2*a(n-1)-a(n-3)+a(n-4).**

*1, 2, 4, 7, 13, 24, 45, 84, 157, 293, 547, 1021, 1906, 3558, 6642, 12399, 23146*

*2 seqfan posts*

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

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