Thanks!  I have read some of the WiKi page till my head got full.  I'll go read more later.

I don't have access to Mathematica, and the documentation in R is a bit more than I want to tackle in the next short while. 

Based on what I have seen, however, I wish I had another plot, this time the Poisson distribution as you have presented it, only for lambda = 18 (3 hour expected network block production), and running out to k = 36. 

While I am wishing, I also want a numeric table of the cumulative distribution function for the same distribution.

If anyone has the R to do this, I would be really appreciative to see it.  While I myself can code this correctly in R from the WiKi definitions, it will take some time.