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A117390
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Numbers n such that 1234567890*sum(k=1,n,10^(10k-9)) + 1 is prime.
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1
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OFFSET
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1,1
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COMMENTS
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The first two terms are given in the linked source in "Table 42: Ten Types of 'Rare' Prime Numbers" for entry "B. Sequential prime of the type: (1234567890)n 1", which designates that 1234567890 is concatenated n times and then 1 is appended. 1888, found by PrimeForm using recurrence mode, corresponds to an 18881-digit probable prime. There are no other terms <= 3000.
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LINKS
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CROSSREFS
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KEYWORD
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bref,hard,more,nonn
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AUTHOR
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STATUS
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approved
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