HP-41 Challenge: Double Integrals by INTEG Recursion

[hth]

I have not calculated an integral for 35 years, and never even heard of the existence of a double.

Sounds like an interesting programming challenge, I assume you want to swap in and out the buffer of the Advantage module, maintaining more than instance of the buffer. I look forward to your article, maybe I will (as you say) find time to take a stab at it, at some point in the future.

Håkan