## BB +> 0.533 * 10 ^ 14780 years

o 4096 ^ 4096 ns: time taken by a 1GHz Turing machine (doing 1 instruction every 1ns) with 6 states, to write all the “1s” it can write, according to the Busy Beaver Problem. Busy Beaver problem: given a Turing machine that stops, how many