Prime number finder HP11C?

[Don Shepherd]

(06-19-2016 05:35 PM)jbhp55 Wrote:  Thank you for teaching me another useful technique!

You are welcome, Jaap.

I am not clever enough to have come up with this idea myself, I learned it from another fellow on this forum, Mike Engle, several years ago.

Mike, are you still around?

Interestingly, if you run this solver equation on the 19bii, you don't have to RCL FACT each time, it will automatically show you each factor as it displays the error message. And, it shows you the original number you started factoring at the beginning, too. Very nice.

But if you ever want to write solver equations, especially complex ones, on the 19bii, be aware that there is a major gotcha: it will not store your equation if it has any errors in it. You must correct the error immediately, unlike the solver in the 17bii which goes on and stores your erroneous equation and lets you fix it later.