Let us quantify your statement! By my calculation, you need to capture 0.9176 carbon atoms from the air to make propane whose energy content is the same as oct

Let us quantify your statement! By my calculation, you need to capture 0.9176 carbon atoms from the air to make propane whose energy content is the same as octane made from 1.0000 captured carbon atoms. I used the "Std enthalpy of combustion (ΔcH⦵298)" of the 2 fuels from Wikipedia in my calculation.