A111393 Number of digits in n^3.

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

Links

Table of n, a(n) for n=1..105.

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

Adjacent sequences: A111390 A111391 A111392 * A111394 A111395 A111396

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