RAID 0 = stripe
RAID 1 = mirror
RAID 5 = single parity
RAID 6 = dual parity
A normal CPG could be Raid 5 (3+1) which means 3 data for each parity. As 3PAR is using wide-striping it is generally considered to be RAID 50 (or 5+0) when multiple 3+1 is used to generate a data set.
Going a bit deeper, each disk in a 3PAR is divided into chunklets (1GB for Gen4 and Gen5 systems). Without the "+0" you wouldn't be able to have a volume (or CPG) larger than 3GB with RAID 5 (3+1).
I would recommend reading pages 42-44 or something in the concepts guide
https://support.hpe.com/hpsc/doc/public ... =c04204225 .