SPRP in base 61 and 71

By form (B^2048+1)/2, I found PRPs for B = 799, 2117, 3109, 9007, 21727, 22047, 22163, 23601, 24681, 24769, 26591, 29609, 33925, 35823, 37107, 46999, 47649, 48439, 54507, 54603, 55009, 59653, 67157, 70809, 79585 and 96515, to B < 10^5.

To be completed...