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 A108697 Numbers n such that a^r + b^r + c^r + ... is prime, where a*b*c* ... is the prime factorization of n and r is the product of the nonzero digits of n. 0
 10, 11, 12, 14, 22, 40, 54, 101, 122, 136, 250, 261, 300, 328, 500, 539, 704, 720, 850, 1001, 1016, 1020, 1110, 1112, 1140, 1210, 1402, 2121, 2211, 2220, 2254, 2400, 3081, 3114, 3311, 4011, 4100, 4180, 4510, 6231, 9093, 10110, 10111, 10112, 10203, 10216 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Of the terms shown, 9093 generates the largest prime, 3^243+7^243+433^243, which has 641 digits. - David Wasserman, May 22 2008 a(74) = 15273. Of the first 74 terms, a(72) = 14464 generates the largest prime, 7*2^384+113^384, which has 789 digits. - David Wasserman, May 22 2008 LINKS EXAMPLE 22 is in the sequence because 22 = 2*11 and 2^(2*2) + 11^(2*2) = 14657, a prime. CROSSREFS Cf. A051801, A082813. A020449 is a subsequence. Sequence in context: A098945 A323190 A046431 * A109279 A258744 A219251 Adjacent sequences:  A108694 A108695 A108696 * A108698 A108699 A108700 KEYWORD base,less,nonn AUTHOR Jason Earls, Jun 19 2005 EXTENSIONS More terms from David Wasserman, May 22 2008 STATUS approved

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Last modified August 4 01:48 EDT 2021. Contains 346441 sequences. (Running on oeis4.)