Which number was almost not used, as per racing tradition in Formula One history?

The number 13 is considered bad luck, but I was born on 13th February (an early Valentine’s present) and have never thought of it in that way .

I call it lucky 13th during my younger years. as an employee. my locker and tool box numbers were both number 13. until I retired these number does not give any problem.

13 is my luckiest number

Gil 0518 99, When I worked in an emergency department that was expanding the Cardiologists would not have a thirteen room number. The emergency department has extended to about fifty beds, still no thirteen.

In Canada we don't have 13th floor or the 13th elevator number.

Hotels in Ireland (not sure about other countries) do not have a 13 room,no 113,213,313,413,superstition

Player #28825483, I too was born on the 13th of February, and even had the 13th anniversary of my entering this life on a Friday the 13th. The number 13 is as lucky as any other. Nothing wrong with the number, unless you are superstitious.

it being unlucky I suppose!

She was also born on Friday the thirteenth, considered a very evil day

As most of you said the number 13 is considered unlucky,probably to hope for no race car accidents. My best friend was also born on the thirteenth and 13 is her lucky number, and she is very lucky. I say that it is only superstitions of some people.