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A273403
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Numbers k such that (10^k - 7^k)/3 is prime.
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0
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OFFSET
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1,1
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COMMENTS
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All terms are prime.
The corresponding primes: 17, 3333280741539321718064461652419, ...
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LINKS
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MATHEMATICA
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Select[Range[1, 10000], PrimeQ[(10^# - 7^#)/3] &]
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PROG
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(PARI) for(n=1, 10000, if(isprime((10^n - 7^n)/3), print1(n, ", ")))
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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