Hello, I have managed to get an Arima model with R but I have not managed to create the mathematical model SARIMA(4,1,1)(0,1,1)_{12}
can you help me create the mathematical model?

I am not sure what you mean by the mathematical model. SARIMA(4,1,1)(0,1,1) is the model that is estimated (except there should be something like a 12,4 etc at the end to say the time periods, which I don't think is what you are asking about).

I am not sure what you mean by the mathematical model. SARIMA(4,1,1)(0,1,1)_{12} is the model that is estimated (except there should be something like a 12,4 etc at the end to say the time periods, which I don't think is what you are asking about).