That's true - you can quite easily prove that an eventually constant sequence of decimals codes for a rational number. But it's also true that pi may not conta

That's true - you can quite easily prove that an eventually constant sequence of decimals codes for a rational number. But it's also true that pi may not contain every _possible_ sequence of decimals, no matter what base you pick. Like the Riemann hypothesis, it seems very likely and people have checked a lot of statistics, but nobody has proven it beyond a (mathematical) shadow of doubt.