Multiply a series values 'on the fly' before presenting in chart.

I would like to multiply a serie in 'series values' (before presenting on a chart) with a factor (in a formula like ='[1]name'!$V$2:$V$148)

in other words I would like to do something like
=('[1]name'!$V$2:$V$148)*50

but I don't seem to succeed with the correct syntax.

In Excel Help searching for "multiply series values" under "edit series" there is to read:
"Use this option to include additional data series on the chart or to modify the name and values of existing data series without affecting the data on the worksheet."

So what I want to do seems to be possible. What am I doing wrong?

Excel 2007 version 12.0.6611.1000

I know I can create a temporary column with the multiplied values but THIS IS NOT the way I want to solve the problem.

Thanks to both Andy Pope and sweep, your solutions work fine and are basically what I have been using: a manipulated temporary 'man in the middle' column.

This is not what I want to use. I want to manipulate directly the series and multiply it 'on the fly' without doing an extra stop on the temporary column.

The chart is built up by the SERIES formula that in my case looks like this:

=SERIES('[Book2]stq day'!$T$1;'[Book2]stq day'!$A$2:$A$148;'[Book2]stq day'!$T$2:$T$148;1)

and what is seen by clicking "edit" in "select data" are the parameters of the SERIES formula.
So what I wish to do is to multiply the cell references in the SERIES formula by a random number.

As far as I can read Excel Helps states that this can be done.

Syntax? Suggestions?