First contact/ aliens story.
I remember a book I read that involved a space shuttle with I think just 3 humans that are traveling to an alien planet where Earth thinks alien life might be. As they get closer to the planet they get contacted by the aliens on the planet. They go through the process of trying to communicate, using prime numbers and math as a starting point. At some point the humans figure out that the aliens are lying and knew the humans were coming. The ship either crashes or one of the people is forced down to the planet which has much higher gravity than earth. The aliens realized they could never leave their planet due to its much higher gravity and wanted to try to steal human technology. I believe the ending was the aliens and humans working together and the humans helping them create a space elevator that could solve the higher gravity problem.
This is bugging me and I appreciate any help!