Does anyone know the equivalent version numbers for Windows NT 3 and 4?

I think the following is correct:

Win95 = 4.0
Win95b = 4.0b
Win98 = 4.10
Win98SE = 4.10a
WinME = 4.90
WinNT3 = ?
WinNT4 = ?
Win2K = 5.0
WinXP = 5.1

Any help would be appreciated.