**a(n) = the least number k such that cos(2pi/k) is an algebraic number of a prime(n)-smooth degree, but not prime(n-1)-smooth.**

*3, 7, 11, 29, 23, 53, 103, 191, 47, 59, 311, 149, 83, 173, 283, 107, 709, 367, 269, 569*

*3 seqfan posts*

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

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