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README.md

@@ -8,6 +8,6 @@ Implementation of the number theoretic transform (NTT) in Rust.
 
 This is a discrete Fourier transform over a finite field of prime order p rather than over the complex numbers.
 
-We generally allow the case of the ring Z/NZ where $N = p^k$ or $2 p^k$. In this case the multiplicative group is cyclic and the order is given by the Euler totient function, $\phi(p^k) = \phi(2*p^k) = p^k(p-1)$. 
+We generally allow the case of the ring Z/NZ where $N = p^k$ or $2 p^k$. In this case the multiplicative group is cyclic and the order is given by the Euler totient function, $\phi(p^k) = \phi(2 p^k) = p^k(p-1)$. 
 
 The array size is `n` and must divide $\phi(p^k)$. If `n` is a power of 2 and $p > 2$, then one must have $n|p-1$.