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A369000
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a(n) is the number of integers, not semiprimes, whose arithmetic derivative is equal to the n-th primorial.
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7
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0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 2, 9, 18
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OFFSET
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1,11
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COMMENTS
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LINKS
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FORMULA
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PROG
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(PARI) \\ See the attached PARI-program.
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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