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

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Last modified March 28 21:02 EDT 2023. Contains 361596 sequences. (Running on oeis4.)