[]
Gets or sets the array formula of a range, using ReferenceStyle.R1C1.
string FormulaArrayR1C1 { get; set; }
Property FormulaArrayR1C1 As String
IRange range = worksheet.Range["A1:A3"];
range.FormulaArrayR1C1 = "=ROW(R1C1:R3C1)";
workbook.Calculate();
object value = worksheet.Range["A1"].Value;