**a(n) = sum{k=1 to n} binomial(n,k) * GCD(k,n).**

*1, 4, 9, 24, 35, 138, 133, 528, 855, 2550, 2057, 12708, 8203, 45178, 78645, 182816*

*2 seqfan posts*

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

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