0,1

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

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

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

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);

Sequence in context: A141743 A112416 A061265 this_sequence A000035 A131734 A134452

Adjacent sequences: A125119 A125120 A125121 this_sequence A125123 A125124 A125125

easy,nonn,base

Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), Jan 10 2007