Question
Give a recursive definition of $w^{i},$ where $w$ is a string and $i$ is a nonnegative integer. (Here $w^{i}$ represents the concatenation of $i$ copies of the string $w . )$
Step 1
The base case is when $i=0$. In this case, we define $w^{0}$ to be $\lambda$, where $\lambda$ is the empty string. This is because any string raised to the power of 0 should result in the empty string. So, we have: \[w^{0} = \lambda\] Show more…
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