How to evaluate finite product of exponential function in path integrals? $\prod_{i=1}^{N-1} \exp(-\omega t_{i})$ with $t_{1}=0$ and $t_{N}=T$. The answer is $\exp(-\omega T/2)$. I have come across these equation while evaluating the path integral of a harmonic oscillator without evaluating action integral. The title of the paper is "An elementary derivation of the harmonic oscillator propagator" The paper is in the following link. https://arxiv.org/abs/physics/0402069
In particular, I want to know how he arrived at equation (6) from equation (5)
