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A092995
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Smallest prime of the form concatenation of prime(n) with itself followed by a 9, or 0 if no such prime exists.
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3
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29, 0, 59, 79, 11119, 139, 179, 199, 239, 29292929292929299, 31319, 379, 419, 439, 479, 0, 599, 619, 67679, 719, 739, 797979799, 839, 89899, 979797979, 1019, 1039, 1071071071079, 1091091091099, 1131139, 1279, 1319, 1371371371379, 1399, 1499
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OFFSET
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1,1
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COMMENTS
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a(16)=0 since the concatenation of 53 with itself, followed by a 9, is always composite. a(36), if it exists, has more than 12000 digits. - Giovanni Resta, Apr 07 2006
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LINKS
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CROSSREFS
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KEYWORD
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base,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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