regex string that would validate specific alphanumeric format

regex string that would validate specific alphanumeric format

I need to validate a specific format of numbers and letters,
What would be the regex string that would check
nnnnnnnnnA (example 123456789A)
I tried ^[0-9]^[0-9]^[0-9]^[0-9]^[0-9]^[0-9]^[0-9]^[0-9]^[0-9]{A-Z}$ but
it's not forcing the 9 number plus one letter