Calculating XP for a 21st level character

[orangefruitbat]

As we approach the end of our Age of Worms capaign, some of the players are hitting 21st level. I understand the rules for calculating XP for monsters with a CR of 21+, but I can't figure out the formula when PCs are level 21+. The table in the DMG only goes to 20.

For instance, if 4 21st level characters defeat 2 CR 19 creatures, what is the XP?

 

[ValhallaGH]

The Epic Level book has a) Another XP chart that goes from Party Level 21 to 40 b) a formula for calculating other xp awards.

For encounters within 1 CR of the party level, use 200, 300 or 400 times CR to determine how much xp to award. For every two points the CR increases above party level multiply by two, and for every two points CR decreases below party level divide by 1/2.

So CR 19 for 21st levels would be about 300*19/2= 2850 xp for the party, by calculation. Two of those are 5700 xp, split amongst the party. For four party members that becomes 1425 xp apiece.