"The average wealth table for Epic characters can be found on page 209 of the DMG v.3.5. You can see a pattern as to how it advances past 40th level, but those numbers are up to the DM's final adjudication."
Wizards customer support.
I thought it was established that there was NO pattern to gold amounts?
THere is a pattern... jsut not all the way from 1 to 40... after lvl 20 the pattern changes to the 21-40+ pattern... based on encounters per lvl, and wealth per encounter
There's no true pattern, however, with an exponential progression you can get pretty close. I did that for 25th level characters before ELH came out, and I was pleased how close I got it.