Yes, the wrong way round. But only after calculating the Statistical Process control parameters "d3" during 15 days, could I use the results to Google for it. I found that I wasn't the first to be frustrated by the 'generally accepted' 3-digit precision in SPC-tables like http://www.ct-yankee.com/spc/ and I wanted to know more, just like http://en.wikipedia.org/wiki/User:NorwegianBlue/refdesk/statistics Had I only found this site during my hours of Google-searching *before* doing the ugly double integral! Anyway, let's say that numerical accuracy to about 10 digits should suffice to uniquely make a floating point constant Googlable. Similar to what Simon Plouffe aspired with smaller hardware in his 'invertor'. http://bootes.math.uqam.ca/cgi-bin/ipcgi/lookup.pl?Submit=GO+&number=0.85250... Wouter. http://users.telenet.be/Wouter.Meeussen/Statistical%20Process%20Control%20d2...