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A050676
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Let b(n) = number of prime factors (with multiplicity) of concatenation of numbers from 1 to n; sequence gives smallest number m with b(m) = n.
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1
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OFFSET
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1,2
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COMMENTS
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a(11) <= 148, a(12) = 104, a(13) = 100, a(14) = 54, a(15) <= 184. - Michael S. Branicky, Dec 14 2022 using factorizations at the De Geest link
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LINKS
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MATHEMATICA
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Join[{1}, Table[i=1; While[PrimeOmega[FromDigits[Flatten[IntegerDigits[Range[i]]]]]!=n, i++]; i, {n, 2, 10}]] (* Jayanta Basu, May 30 2013 *)
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CROSSREFS
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KEYWORD
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nonn,base,hard,more
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AUTHOR
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STATUS
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approved
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