In option pricing when the binomial result equal to black scholes result?

In option pricing when the binomial result equal to black scholes result?
When the binomial tree has a large numbers of steps (i.e. the time interval between nodes is very small).
The spreadsheet in the related link prices options using Black-Scholes analytical equations and a binomial tree. As the number of steps in the binomial tree increase, the results of both approaches becomes equal to many decimal places.