Vikramaditya will not carry 30 mig29, the same way liaoning won't usually carry more than 24 J15. Instead of trusting dubious sources, why not just look at available imagery? Using the same standard for both ships of having the landing strip free, take off strip free and both elevators free - it is very clear one can put around 12-13 or so mig29 in the hangar inside vikramadity and another 11-12 or so on the deck (leaving little space for helicopters).
Basically, 24 mig29k plus 6 or so helicopters for a total of 30 aircraft.
Liaoning can embark some 15 j15 in hangar plus another 10-11 on deck - while leaving all three take off points empty. In theory, Liaoning has the luxury of parking planes on right-side take off strip for a few more planes but in reality that wouldn't be used.
To conclude, Liaoning can carry at least as many j15 as vikramaditya can carry mig29k. With a bit additional room to spare, even 26 j15 (plus 6 helicopters) could be doable.
