Before revision:  In contrast with the four-currency case, we find that arbitrage operations when d >= 5 currencies are present may appear very unstable, with the exchange rates growing in accordance with the double exponential law !
After revision:  In contrast with the four-currency case, we find that arbitrage operations when d >= 5 currencies are present may appear very unstable, with the exchange rates growing in accordance with the double exponential law may additionally apply. There is an "inheritance of instability" in the higher-order currency worlds. Profitable arbitrage operations are thus endemic rather that displaying the self-extinguishing properties implied by the EMH.