What's the equation for energy production?

Energy wouldn’t be produced, it would be absorbed by the liquid Nitrogen. The energy absorbed can be calculated by knowing Nitrogen’s specific heat and heat of evaporation.

E=MC² …that could be very wrong though im not a physicist or chemist

Here’s how you find it.
Find the density of Liquid Nitrogern at 73K.
Multiply by the number of ml you have to get grams.
Now find the specific heat of liquid nitorgen. Multiply that by the number of grams above.
Find the heat of vaporization. Multiply that mby the number of grams above.
Add the two and you have the mount of energy it takes to evaporate your sample.
You are not generating energy. Only moving in from one place to another.

You aren’t actually looking for how much energy is produced. That would be none. Energy would be absorbed from the relatively warm air into the very cold LN2 till it all boils away. No energy would be generated or destroyed in this process.