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A106125
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Numbers k such that k divides the k-th semiprime.
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2
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1, 2, 3, 7, 11, 43, 53, 613367, 613439, 613451, 613523, 613549, 613609, 6384425461, 6384425521, 6384425569, 6384425647
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OFFSET
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1,2
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COMMENTS
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Note that except 1, all other term in the sequence will be primes.
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LINKS
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EXAMPLE
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a(4)=7 is a term because 7 divides the 7th semiprime (i.e., 21).
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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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EXTENSIONS
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STATUS
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approved
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