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 A087556 a(n) = smallest prime that is the concatenation of two numbers whose sum is n. 1
 11, 0, 13, 23, 0, 43, 17, 0, 19, 29, 0, 67, 59, 0, 79, 89, 0, 109, 137, 0, 139, 149, 0, 223, 179, 0, 127, 227, 0, 229, 131, 0, 277, 233, 0, 307, 137, 0, 139, 239, 0, 241, 359, 0, 379, 389, 0, 409, 149, 0, 151, 251, 0, 487, 353, 0, 157, 257, 0, 457, 359, 0, 163, 263, 0, 463 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS a(3k) = 0. Conjecture: No other term is zero. LINKS EXAMPLE a(10) = 19, the Partitions of 10 are (1,9), (2,8), 3,7), (4,6), (5,5) and the primes obtained are 19,37 and 73. CROSSREFS Cf. A087555. Sequence in context: A271572 A180059 A147765 * A082268 A087557 A186072 Adjacent sequences: A087553 A087554 A087555 * A087557 A087558 A087559 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 December 1 09:36 EST 2022. Contains 358467 sequences. (Running on oeis4.)