Recursive Formulas

Has anyone been able to create a recursive formula with a purely node-based approach? I need to create a function where each value in a list adds to the previous value until the full list has been processed. I am trying to evenly space geometry from a list by calculating the width of the previous item and adding a “spacer” value, so each subsequent calculation is dependent on the one before. Here is an example of the outcome I am looking for:

recursive wishlist explanation_def





A few individuals have directed me to a Python approach that works but I would like to see if it is possible with Dynamo nodes alone. I have seen a few examples where custom nodes (a sequence grouped into one node) have an instance of the custom node nested within itself to create a loop but don’t fully understand how to achieve this. Another possibility may be the Loop While node, can someone elaborate on how this node works?

If there are existing Forum threads that have already addressed this, please feel free to point me in the right direction. Thanks!

Again, I would just use LunchBox’s Mass Addition node:


Andreas, once again you come through with the perfect solution. Building on the Lunchbox Mass Addition node and the example you provided above, I was able to figure out exactly what I was looking for. Thank you.

recursive definition_SOLVED