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A046760
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Wasteful numbers.
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7
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4, 6, 8, 9, 12, 18, 20, 22, 24, 26, 28, 30, 33, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 99, 100, 102, 104, 108, 110, 114
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Write n as product of primes raised to powers, let D(n) = number of digits in product, l(n) = number of digits in n; sequence gives n such that D(n)>l(n).
A050252(a(n)) > A055642(a(n)). [Reinhard Zumkeller, Jun 21 2011]
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LINKS
| J.-P. Delahaye, Les chasseurs de nombres premiers
R. G. E. Pinch, Economical numbers.
Eric Weisstein's World of Mathematics, Wasteful Number.
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
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EXAMPLE
| For n=125=5^3, l(n)=3 but D(n)=2.
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MATHEMATICA
| Cases[Range[115], n_ /; Length[Flatten[IntegerDigits[FactorInteger[n] /. 1 -> Sequence[]]]] > Length[IntegerDigits[n]]] (* Jean-François Alcover, Mar 21 2011 *)
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CROSSREFS
| Cf. A046758, A046759.
Sequence in context: A028958 A200878 A036310 * A115684 A020201 A161760
Adjacent sequences: A046757 A046758 A046759 * A046761 A046762 A046763
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KEYWORD
| nonn,nice,base,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| More terms from Eric Weisstein (eric(AT)weisstein.com).
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