Have you tried ML.NET?
It's a new machine learning framework made specifically for .NET developers.
.NET Core Preview
Want to try out the latest preview? .NET Core 3.0.0-preview-27122-01 is available.

.NET Framework 3.5 SP1 downloads

Not sure what to download? Head to our main Downloads page to find recommended downloads for the latest version of .NET.

.NET Framework 3.5 SP1  Build apps - Dev Pack  Run apps - Runtime
Web installer  N/A Runtime

Looking for a different version? See the download archives.