yer werds belo dont match hedline, so dont no start point . . . maebee yu want 11*[sum(1/3)^n, n=1, infinity] ????? . . . (1/3)+(1/9)=0.44444444444444... . . . 1/27=0.037037037...sum=0.48148148148... 1/81=0.0123456789...sum=0.49382716 . . . me ges sum=0.5