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A069716
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Smallest number such that the LCM of the digits equals n, or 0 if no such number exists.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 9, 25, 0, 34, 0, 27, 35, 0, 0, 29, 0, 45, 37, 0, 0, 38, 0, 0, 0, 47, 0, 56, 0, 0, 0, 0, 57, 49, 0, 0, 0, 58, 0, 67, 0, 0, 59, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 78, 0, 0, 0, 345, 0, 0, 79, 0, 0, 0, 0, 0, 0, 257, 0, 89, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 347, 0, 0, 0, 0, 0, 259, 0, 0
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OFFSET
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1,2
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COMMENTS
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If n is a prime with more than one digit, a(n) = 0. - Alonso del Arte, Dec 20 2015
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LINKS
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EXAMPLE
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a(20) = 45 because lcm(4, 5) = 20. If one solution exists, then an infinite number of solutions exist. For n = 20, e.g., 455, 445555555, 545544 etc. are also solutions.
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MATHEMATICA
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digLCMSeek[x_] := Apply[LCM, IntegerDigits[x]]; A069716 = Table[0, {256}]; Do[s = digLCMSeek[n]; If[s < 257 && A069716[[s]] == 0, A069716[[s]] = n], {n, 10000}]; A069716
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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