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A168117
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Primes whose indices are perfect numbers.
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0
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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a(1)=13 because the first perfect number is 6 and the 6th prime is 13.
a(2)=107 because the second perfect number is 28 and the 28th prime is 107.
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CROSSREFS
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KEYWORD
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hard,more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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