SPRP in base 79 and 83 For base 62, I found hitherto: (62^3-1)/61 (62^5-1)/61 (62^17-1)/61 (62^47-1)/61 (62^163-1)/61 (62^173-1)/61 (62^757-1)/61 (62^4567-1)/61 (62^9221-1)/61
To be completed...