The Hendricks-McAfee Merger Simulator
AlphaDemand Elasticity (negative value gives infinity)
BetaDownstream Cost Elasticity
EtaUpstream Cost Elasticity
ThetaIntermediate/Final Price Ratio
nNumber of Firms
Type1 = "Firm 1 + 2", 2 = 1 + Firm 2's downstream, 3 = 1 + Firm 2's upstream

Notes: Input variables have pink backgrounds.
The Hendricks-McAfee Bilateral Oligopoly Paper
The Shares Computer, which takes capital values as inputs.

This page with up to 20 firms.