First of all, there are some general things that are recommended for any type of memorization. 1. My theater classes told me to memorize the last line of my script first, so that it would be the most practiced over time and, rather than getting nervous or self-unconfident as I approached the end, I would know that the easier part was coming up and would finish confidently. 2. Try a kinetic approach. Once I learned to count to 10 in sign language, I found I could hold the numbers on my hand instead of in my brain. And, a kinetic learning style (basically, shaking my hand) helped me remember phone numbers, etc. If you're a visual learner, write the numbers or stare at them. If you're an auditory learner, say the numbers.
I remember in an old psychology class learning about experiments they did with memory. A regular guy learned to be able to repeat back hundreds of digits. He did it by associating different things with the numbers; for example, area codes, birthdays, and the uniforms of favorite baseball players. Do you know anybody born in '92? There's 2 of your ten digits. "Columbus sailed the ocean blue in 1492" is also in there, if you can remember to stick a 15 in the middle. Or maybe you're 26 years old? You get the point. :) From there, you could link some mental pictures to tell a story.
Let's see... 3.1415926535 ... 3 is like 13, 14, 15. I work 9 to (2) 6. In 5 years I'll be 35 years old.
Or, if you can handle out of order, we have 13, 14, 15. 9 - 6 - 3 is multiples of 3 backwards. In between we have 2 5s (2 5 5). Just as an example.
Or, if I misunderstood the question, I could say that the value of pie is measured by the company who eats it with you. :-)
