Air solubility in hydrocarbons is frequently expressed by the Ostwald coefficient, which for air at 273 K is 0.095. This coefficient gives the volume of gas per volume of liquid solvent.
I assume that this is not a constant for every crude, but may give you a "grosso modo" idea of the true value.
Correction formulas for other temperatures can be found, for example, in Stachowiak and Batchelor's Engineering Tribology Tribology Series, 24 (Elsevier).
There is no formula here, except for the conversion of the Ostwald coefficient at 273 K, C[sub]0[/sub], to C[sub]T[/sub] at temperature T.
Pressure doesn't play a role since gas solubility is generally proportional to gas pressure, and assuming the ideal gas law applies, pressure effects cancel out. Meaning that 95 L of air per 1000 L of hydrocarbon at 1 atm should be the same at 2 or 3 atm, all measured at 0[sup]o[/sup]C.
According to the reference given above the Ostwald coefficient is evaluated according to ASTM D2779-92(2007). Don't be surprised to find that solubility of air in hydrocarbons may actually increase with temperature to a certain degree.