Question 984970
So the first three numbers can take on {{{467-449+1+745-727+1=38}}} possible choices.
The remaining 6 numbers can take on any digit 1-9 so that makes a total of,
{{{N=9*9*9*9*9*9=9^6=531441}}} possible choices. 
So then the total 9 digit numbers assigned to Texas are,
{{{N[9]=38*531441=20194578}}}
They may run out of numbers but new SSN's are only issued for births and new citizens so it's difficult to make on decision based only on population.