**a(1)=2, a(2)=3, for n>=3, a(n)=2*(gpd(a(n-1))+gpd(a(n-2)))+1, where gpd(n) is the greatest prime divisor of n.**

*2, 3, 11, 29, 81, 65, 33, 49, 37, 89, 253, 225, 57, 49, 53, 121, 129, 109, 305, 341, 185*

*3 seqfan posts*

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

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