Any way to do @NSUM function in Excel?

[Tom Hayakawa]

In Lotus 123 there is a function called @NSUM, which
allows you to sum every nth value (eg, sum the series of
cells starting at B3, and then every third cell right of
the C3 for 15 columns). The form was something like
this: @NSUM(b3,3,15). Does anyone know of a similar
function in Excel, or an easy way to set up a sum formula
to behave that way? Thanks.

 

[Dave R.]

Hi-

=SUM(IF(MOD(ROW(A1:A11),2)=1,A1:A11))

array entered (control shift enter). The first cell summed will be A1, it
will skip A2, but add A3, A5, A7, A9, A11.

Change the ",2" part to ",3" if you want every 3rd cell in the range
(a1,a4,a7, etc).

 

[Tom Hayakawa]

Thanks for the quick reply. Ingenius answer, thanks!