Solving for $\log^*n$ I know the iterative logarithm can only produce 1 of 6 numbers. However, I don't really understand how to solve. Can someone please explain how to solve $\log^*n$ where $n$ is any number, lets say like 100. Would there be any difference for $\lg^*n$?

There I a huge difference between $\log_{10} n$ and $\log_2 n$.Let the first value be $x$ and the second be $y$.Then $n=2^x$ and $n=10^y$.That's why The value of $x$ and $y$ after different.
To solve it you have to write $n$ as a power of $10$.
Examples:1) $\log_{10} 100=\log_{10} 10^2=2$
2)$\log_{10} 200=\log_{10} 100 + \log_{10} 2=2+\log2$
