You can grep the web for Dik's original version. The 3-line homage version I linked contains both his full name and the name of the algorithm used: "spigot" (as in spew, faucet), which itself contains the letters PI. In addition, this version outputs exactly 31416 digits of pi. So it's triple self-referential. Happy 2022.03.14 pi day to all.
Which spigot algorithm is the 3-line version using exactly? (I did some untangling of the code in limited time, but it's still pretty cryptic.)
The original pi/spigot work was done by Rabinowitz & Wagon [1]. See also the very readable works by Jeremy Gibbons [2] [3].