**a(n) = 6*a(n-1) - a(n-2) + 2 with a(0) = 0, a(1) = 3.**

*0, 3, 20, 119, 696, 4059, 23660, 137903, 803760, 4684659, 27304196, 159140519*

*1 seqfan posts*

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

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