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A174710
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Numbers n such that n*10^n + (10^n - 1)/3 is prime.
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1
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OFFSET
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1,2
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COMMENTS
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No term is a multiple of 3. The decimal expansion of each corresponding prime is n's decimal expansion with n 3's concatenated. Primes and probable primes found by PrimeForm. Primes for 275 and 1556 proved by Primo. No more terms up to 30000.
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LINKS
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EXAMPLE
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The numbers 1 and 2 are terms because 13 and 233 are prime.
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PROG
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CROSSREFS
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Cf. A068817 (n followed by n 1's is prime), A133127 (n followed by n 7's is prime), A174352 (n followed by n 9's is prime).
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KEYWORD
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more,nonn
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AUTHOR
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STATUS
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approved
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