**a(n)=1/(4i)*sum( i^k*tan(k*Pi/4/n)) where 1<=k<=n and (k,n)=1.**

*1, 2, 2, 2, 4, 4, 4, 6, 4, 6, 8, 6, 8, 8, 8, 8, 12, 10, 8, 16, 12, 12, 16, 10*

*2 seqfan posts*

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

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