The series is S = Sum 1 / (k * (k + 1) * (k + 2)). Once cut in three parts it is established it converges toward 1/4.

Then we fired up Dr. Geo to compute a few ten of thousand terms and its sum.

In a Workspace we wrote this tiny script:

| u s |
u := [ :k| 1 / (k * (k + 1) * (k + 2) ) ].
s := 0.
1 to: 100000 do: [ :k | s := s + (u value: k) ].
Transcript show: s; tab; show: s asFloat; cr

...and we got the confirmation of our finding:

(1250037500/5000150001) 0.2499999999500015

What is interesting is the exact result Pharo gave us as a fraction number. That's why we also asked for a float version of the sum to more easily realize how close we were to 1/4.