One small nitpick: Although I agree with your solution (and it is well explained), it is only valid for a 2-Dimensional pizza. If it is 3-dimensional, it can be sliced through the centre three times so that for n=3, x=8.
blackjack
<a href="http://c.casalemedia.com/c?s=51816&f=3&id=0" target="_blank"><img src="http://as.casalemedia.com/s?s=51816&u=http://perplexus.info&f=3&id=0&if=0" width="120" height="600" border="0"></a>
flooble's webmaster puzzle
re: full solution
