**a(0) = 1; for n > 0, a(n) = smallest positive integer whose prime signature contains, for k = 1 to n, exactly one positive number appearing exactly k times.**

*1, 2, 60, 1801800, 11657093261814000, 7167827541370578634694420017740000*

*1 seqfan posts*

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

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