A125122 First differences of A034888.

0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0

Offset

0,1

Comments

This sequence is not periodic because log(3)/log(10) is an irrational number. - T. D. Noe, Jan 10 2007

Links

Table of n, a(n) for n=0..104.

Formula

a(n)=Number_of_digits{3^(n+1)}-Number_of digits{3^(n)} with n>=0.

Example

a(1)=0 because 3^(1+1)=9 (one digit) 3^1=3 (one digit) and the difference is 0
a(4)=1 because 3^(4+1)=243 (three digits) 3^(4)=81 (two digits) and the difference is 1

Maple

P:=proc(n) local i, j, k, w, old; k:=3; for i from 1 by 1 to n do j:=k^i; w:=0; while j>0 do w:=w+1; j:=trunc(j/10); od; if i>1 then print(w-old); old:=w; else old:=w; fi; od; end: P(1000);

Mathematica

Differences[IntegerLength[3^Range[0, 110]]] (* Harvey P. Dale, Jan 28 2015 *)

Crossrefs

Sequence in context: A260393 A360113 A361123 * A000035 A188510 A131734

Adjacent sequences: A125119 A125120 A125121 * A125123 A125124 A125125

Keyword

easy,nonn,base

Author

Paolo P. Lava and Giorgio Balzarotti, Jan 10 2007

Status

approved