PRP 2,3,5,7,11,13

This is the smallest base -356 repunit (probable) prime with at least 3 1s.

For the smallest repunit prime with at least 3 1s in all bases -400<=b<=400, b is not a perfect power, some large primes were found (exponent >= 5000, sorted by exponent)

(152^270217-1)/151
(18^25667-1)/17
(53^21943+1)/54
(124^16427+1)/125
(333^9743-1)/332
(356^7937+1)/357
(340^7001+1)/341
(150^6883+1)/151
(318^6733+1)/319
(381^6659+1)/382
(205^5449+1)/206
(230^5333-1)/229

There are no known repunit primes with at least 3 1s were found in bases -373, -365, -335, -316, -309, -306, -304, -284, -220, -188, -187, -186, -175, -113, -103, -97, 184, 185, 200, 210, 269, 281, 306, 311, 326, 331, 371, 380, 384, 385, 391, 394, 396,

To be completed...