**a(n)=6a(n-2)-a(n-4).**

*1, 1, 2, 4, 11, 23, 64, 134, 373, 781, 2174, 4552, 12671, 26531, 73852, 154634*

*1 seqfan posts*

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

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