Do Vice City and San Andreas count as mainline? What about the City Stories or the London games?

According to Wikipedia these are the mainline games, but is this accurate?

Grand Theft Auto
Grand Theft Auto 2
Grand Theft Auto III
Grand Theft Auto: Vice City
Grand Theft Auto: San Andreas
Grand Theft Auto IV
Grand Theft Auto V

Yes, I'd say so. Non-mainlain would be the PSP stories games.

Of course Vice City and San Andreas are mainline, they were huge hits. It doesn't matter that they've not got a number in their name IMO, as they aren't direct sequels, etc.

And at a guess we will get a Vice City GTA this gen, and only that due to GTA5 being so late last gen and crossing over into this.

It would be crime not to include San Andreas.

Vice City and San Andreas didn't have numbers, but they were definitely mainline.