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A191291
The number of bases >=2 in which n is 3-digit number.
2
0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5
OFFSET
1,16
FORMULA
a(n) = floor(sqrt(n))-floor(n^(1/3)) = A000196(n) - A048766(n).
MATHEMATICA
Table[Floor[Sqrt[n]]-Floor[CubeRoot[n]], {n, 90}] (* Harvey P. Dale, Mar 22 2023 *)
PROG
(PARI) a(n)=sqrtint(n)-floor((n+.5)^(1/3)) \\ Charles R Greathouse IV, Jan 03 2013
CROSSREFS
Cf. A191279.
Sequence in context: A328680 A256707 A151963 * A131841 A309432 A230261
KEYWORD
nonn,easy,base
AUTHOR
Vladimir Shevelev, May 29 2011
STATUS
approved