From the Naming Your Child: Guidance for Vermont Birth Certificates sheet:
“The name should use only letters, and should not include numbers in it. As with other alphabets, if you want to include a number in your child’s name, you should spell it out in letters. For example, use Numerouno or Childnumbereight, but not Roger47 or 101110.”
So, I guess our first name pick of #808080 is out. Damn, guess we’ll just have to go with “Gray”!