You will be shown an excerpt from a computer science scientific research paper, followed by a question about the paper. Please answer the question. Do not include any text in your response other than the answer.

Context: We performed 27 random searches (one for each combination of the nine variants and three datasets).Each random search encompasses 200 trials for a total of 5400 trials of randomly sampling the following hyperparameters:•number of LSTM blocks per hidden layer:log-uniform samples from [20,200];•learning rate:log-uniform samples from [10^{-6},10^{-2}];•momentum:1-\text{log-uniform samples from $[0.01,1.0]$};•standard deviation of Gaussian input noise:uniform samples from [0,1].

Question: What hyperparameters do each of the eight variants of LSTMs investigated by the authors of this paper have?
The authors investigated 1) number of LSTM blocks per hidden layer 2) learning rate 3) momentum 4) standard deviation of Gaussian input noise with random searches with uniform sampling.