You're using an LLM as if you don't understand how or why it works. Math is not what it's for. Here, look at what ChatGPT 4 does (for a case that hasn't been fed to it by a hundred other users yet):
What is the sum of odd numbers in this set: 12345654321, 123456543212, 123456543213, 12345654324? Output only the sum, no code.
The sum of the odd numbers in the set {12345654321, 123456543212, 123456543213, 12345654324} is 246913086434.
What does that prove? Only that I am using an LLM poorly and/or do not understand what it is. Using OpenChat-3.5 for what LLMs are actually good at (e.g. asking it for shell commands to perform certain operations, getting some general information about a topic) seems to work surprisingly well for a 7B model.