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A095289
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a(n) = the smallest number (in base 10) such that the product of its digits is >= n.
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1
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1, 2, 3, 4, 5, 6, 7, 8, 9, 25, 26, 26, 27, 27, 28, 28, 29, 29, 37, 37, 37, 38, 38, 38, 39, 39, 39, 47, 48, 48, 48, 48, 49, 49, 49, 49, 58, 58, 58, 58, 59, 59, 59, 59, 59, 68, 68, 68, 69, 69, 69, 69, 69, 69, 78, 78, 79, 79, 79, 79, 79, 79, 79, 88, 89, 89, 89, 89, 89, 89, 89, 89
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OFFSET
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1,2
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COMMENTS
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This seems to be a nondecreasing sequence, at least to 10^5. - Robert G. Wilson v, Jul 05 2004
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REFERENCES
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ARML 2002, Team event, Question 1.
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LINKS
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EXAMPLE
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a(13) = 27 because 2*7 = 14 >= 13 and no number smaller than 27 has this property.
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MATHEMATICA
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f[n_] := Block[{k = n}, While[Times @@ IntegerDigits[k] < n, k++ ]; k]; Table[ f[n], {n, 75}] (* Robert G. Wilson v, Jul 05 2004 *)
Module[{nn=100, pd}, pd=Table[{n, Times@@IntegerDigits[n]}, {n, nn}]; Table[SelectFirst[pd, #[[2]]>= k&], {k, 80}]][[;; , 1]] (* Harvey P. Dale, Jul 25 2023 *)
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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Sam Handler (sam_5_5_5_0(AT)yahoo.com), Jul 02 2004
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EXTENSIONS
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STATUS
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approved
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