[]
Gets or sets the formula for the object using R1C1-style notation.
Use this property to retrieve the series formula when you need row-and-column relative references instead of A1-style references. To work with the formula in A1-style notation, use Formula.
string FormulaR1C1 { get; set; }
Property FormulaR1C1 As String
worksheet.Range["A1:B4"].Value = new object[,] {{"Month", "Sales"}, {"Jan", 12}, {"Feb", 18}, {"Mar", 15}};
IChart chart = worksheet.Shapes.AddChart(ChartType.ColumnClustered, 20, 20, 300, 200).Chart;
chart.SeriesCollection.Add(worksheet.Range["A1:B4"]);
ISeries series = chart.SeriesCollection[0];
string formula = series.FormulaR1C1;