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A030099
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Numbers k such that k^3 has only odd digits.
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5
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1, 11, 15, 33, 39, 71, 91, 173, 175, 179, 211, 259, 335, 3337, 4631, 5597, 7353, 12415, 21353, 22893, 25799, 69491, 110011, 124975, 199831, 227353, 237151, 462815, 492415, 708415, 1100033, 2393695, 2620611, 5088493, 5828415, 7204417, 8320335, 11164415, 11689633
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listen;
history;
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internal format)
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OFFSET
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1,2
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LINKS
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Giovanni Resta, Table of n, a(n) for n = 1..563 (terms < 10^19, first 75 terms from Reinhard Zumkeller, terms 76..151 from Max Alekseyev)
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MATHEMATICA
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fQ[n_] := Union@ OddQ@ IntegerDigits[n^3] == {True}; Select[2 Range[3*10^6] - 1, fQ] (* Robert G. Wilson v, Aug 13 2011 *)
Select[Range[12*10^6], AllTrue[IntegerDigits[#^3], OddQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Apr 14 2015 *)
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PROG
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(Haskell)
import Data.List (intersect)
a030099 n = a030099_list !! (n-1)
a030099_list = filter (null . (intersect "86420") . show . (^ 3)) [1, 3..]
-- Reinhard Zumkeller, Aug 13 2011
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CROSSREFS
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Cf. A000578, A030100, A034376, A052004.
Sequence in context: A009407 A009433 A275242 * A085597 A316643 A097512
Adjacent sequences: A030096 A030097 A030098 * A030100 A030101 A030102
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KEYWORD
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nonn,base,nice
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AUTHOR
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Patrick De Geest
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STATUS
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approved
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