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A215641
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Smallest prime whose decimal expansion consists of the concatenation of a 1-digit prime, a 2-digit prime, a 3-digit prime, ..., and an n-digit prime.
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12
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2, 211, 211151, 2111011129, 211101100910009, 211101100910007100049, 2111011009100071000031000453, 211101100910007100003100000310000721, 211101100910007100003100000310000019100000543, 2111011009100071000031000003100000191000000071000000531
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OFFSET
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1,1
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COMMENTS
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It is a plausible conjecture that a(n) always exists.
a(n) has A000217(n) = n*(n+1)/2 digits.
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LINKS
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EXAMPLE
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a(4) = 2111011129, the smallest prime formed from a single-digit, a double-digit, a triple-digit, and a quadruple-digit prime, i.e., 2, 11, 101, 1129.
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CROSSREFS
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Cf. A338968 (similar, with largest prime).
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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