initial_value: The start value for accumulator. Eg., 1
array: The array given as input. Eg., A2:A8
lambda: The function to be applied to each value in the given array.
accumulator: The total value returned as result. Eg., a
value: A variable indicating the values to be used in calculation. Eg., b
calculation: The calculation used on each value in the array. Eg., a+b