Main Series Games
Red, Green (JP), Blue, Yellow = 453
Gold, Silver, Crystal = 753
Ruby, Sapphire, Emerald = 1158
FireRed and LeafGreen = 772
Diamond, Pearl and Platinum = 1479
HeartGold and SoulSilver = 986
Black and White = 1298
Black and White 2 = 1298
X and Y = 1436
Omega Ruby and Alpha Sapphire = 1436
Add that up and that makes... 11,069 entries to complete!
These are for the National Pokedex entries.
If you want me to do the spin-offs I hate you. I'll do them.
Hope I helped. :)
Source, Experience and Google Calculator.