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A087341
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Smallest prime which is a concatenation of n successive composite numbers.
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2
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89, 138140141, 87889091, 8890919293, 141516182021, 122123124125126128129, 121122123124125126128129, 707274757677788081, 21222425262728303233, 206207208209210212213214215216217, 405406407408410411412413414415416417
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OFFSET
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2,1
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COMMENTS
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a(3) contains three digit composite numbers as every concatenation of two digit numbers n,n+2 and n+3 is == 0 (mod 7).
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LINKS
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Table of n, a(n) for n=2..12.
G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 138140141.
G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 87889091.
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EXAMPLE
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a(2) = 89 is the concatenation of two successive composite numbers 8 and 9.
a(3) = 138140141 is the concatenation of 138,140 and 141.
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CROSSREFS
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Cf. A002808.
Sequence in context: A243316 A072314 A087538 * A093405 A348166 A221307
Adjacent sequences: A087338 A087339 A087340 * A087342 A087343 A087344
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KEYWORD
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base,nonn
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AUTHOR
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Amarnath Murthy, Sep 06 2003
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EXTENSIONS
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More terms from David Wasserman, May 10 2005
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STATUS
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approved
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