American scheme: XXillion = 10^3*(XX+1)
European scheme: XXillion = 10^6*XX = million^XX

European scheme, Danish supplemental:
XXillion = 10^6*XX
XXilliard = 10^6*XX+3 = XXillion*1000

Where XX is a contracted form of the number in bastardized latin.

The american scheme is consistent but not really logical.
Calling it a billion because you started with a thousand and then multipled that with a thousand two times seems like an off-by-one error to me.

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