**a(n) is the least number such that the set {p_1,p_2,...,p_a(n)} contains all residues modulo p_n (p_m is m-th prime).**

*2, 4, 8, 10, 14, 27, 27, 43, 33, 66, 64, 85, 75, 90, 163, 111, 127, 178, 170, 145, 172*

*3 seqfan posts*

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

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