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A247794
a(n)^3 is the least cube to contain exactly n distinct digits.
1
0, 3, 5, 12, 22, 59, 135, 289, 1018, 2326
OFFSET
1,2
COMMENTS
"...at least n..." and "...exactly n..." yield the same sequence (i.e. this sequence is strictly increasing).
MATHEMATICA
With[{cbs=Table[{n, Count[DigitCount[n^3], _?(#>0&)]}, {n, 2500}]}, Join[{0}, Transpose[Table[SelectFirst[cbs, #[[2]]==i&], {i, 2, 10}]][[1]]]] (* The program uses the SelectFirst function from Mathematica version 10 *) (* Harvey P. Dale, Aug 20 2015 *)
PROG
(PARI)
a(n)= k=0; while(#vecsort(digits(k^3), , 8)!=n, k++); k
vector(10, n, a(n))
CROSSREFS
Cf. A054039.
Sequence in context: A368858 A013498 A161624 * A034758 A215109 A131322
KEYWORD
nonn,fini,full,base,easy
AUTHOR
Derek Orr, Sep 23 2014
STATUS
approved