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A111393
Number of digits in n^3.
4
1, 1, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7
OFFSET
1,3
FORMULA
a(n) = floor( (3*log_10(n)) + 1).
a(n) = A055642(n^3). [R. J. Mathar, Mar 05 2010]
EXAMPLE
a(10) = 4
MAPLE
A055642 :=proc(n) max(1, ilog10(n)+1) ; end proc: A111393 := proc(n) A055642(n^3) ; end proc: seq(A111393(n), n=1..90) ; # R. J. Mathar, Mar 05 2010
MATHEMATICA
Array[IntegerLength[#^3]&, 110] (* Harvey P. Dale, Dec 26 2014 *)
PROG
(PARI) a(n)=if(n==0, 1, #digits(n^3)); \\ Joerg Arndt, Mar 30 2014
CROSSREFS
Sequence in context: A072643 A130260 A276621 * A323665 A062537 A279596
KEYWORD
base,nonn
AUTHOR
Salim Erinc (eryigit(AT)boun.edu.tr), Nov 11 2005
EXTENSIONS
Extended by R. J. Mathar, Mar 05 2010
STATUS
approved