www.mikescher.com/www/statics/euler/Euler_Problem-064_explanation.md

For this I had to re-use my old integer-squareroot implementation and I ported an algorithm for calculating the continued fraction to befunge.

The rest is just iterating through all the values and trying to optimize for speed.

Here two useful snippets I made while solving this puzzle:

• Calculating the sum of an zero-terminated array on the stack: >\# :#+_+
• Calculating the count of an zero-terminated array on the stack: 0>\#+ #1:#$_$