Nested radical approximation of PI and PI day on the forum

[pier4r]

Reading the formula of this paper: https://web.archive.org/web/201107062156...ers/pi.pdf (A nested radical approximation for π , version of Jul 6 2011 in the web archive) I remembered that here plenty of such a formulas are shared every year (more or less).

Could it be that π ≈ sqrt(7 + sqrt(6 + sqrt(5))) was found by some users of the forum independently? If I am not wrong for PI day (and even when it is not PI day) a lot of those formulas are posted and computed.

All this was started by this tweet: https://twitter.com/abakcus/status/16864...78688?s=20