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 A087557 a(n) = smallest prime that is the concatenation of two numbers whose product is n. 1
 11, 0, 13, 41, 0, 23, 17, 0, 19, 101, 0, 43, 113, 0, 53, 0, 0, 29, 191, 0, 37, 211, 0, 83, 251, 0, 127, 47, 0, 103, 131, 0, 113, 0, 0, 0, 137, 0, 139, 401, 0, 67, 431, 0, 59, 223, 0, 163, 149, 0, 151, 521, 0, 227, 0, 0, 157, 229, 0, 601, 0, 0, 79, 641, 0, 223, 167, 0, 233, 107, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS a(3k+2) = 0. - David Wasserman, Jun 07 2005 LINKS EXAMPLE a(10) = 101, the pair of complementary factors of 10 are (1,10), (2,5) and the primes obtained are 101. CROSSREFS Cf. A087558. Sequence in context: A147765 A087556 A082268 * A186072 A299780 A297873 Adjacent sequences: A087554 A087555 A087556 * A087558 A087559 A087560 KEYWORD base,nonn AUTHOR Amarnath Murthy, Sep 13 2003 EXTENSIONS More terms from David Wasserman, Jun 07 2005 STATUS approved

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Last modified November 26 18:21 EST 2022. Contains 358362 sequences. (Running on oeis4.)