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by AnotherGoodName 460 days ago
There likely is a trick but the above is also technically feasible as-is.

You have to do this for 10^10 (ten billion) powers. Each operation needs to check ~4.3billion decimal digits at worst (half that on average). It's highly parallelizable since each power is an easy to compute binary digit and you can do a binary->decimal conversion without relying on previous results which is a log(n) operation, ie one operation per decimal digit.

All up 10^10 powers * ((10^4.3)/2) decimal digits to calculate and check for each of those powers. Around 200 trillion operations all up in human terms. It's still hard enough you'd want a lot of compute. Getting each operation down to a nanosecond still means you're waiting 2.3days for a result. But it's also fair to say it's feasible.

1 comments

> and you can do a binary->decimal conversion without relying on previous results which is a log(n) operation, ie one operation per decimal digit

Aren't those operations divisions? One division would usually be considered more than one operation.