WinPFGW 3.7.10:
2^170641-4411 is 3-PRP! (14.9729s+0.0002s)
2^178343-4447 is 3-PRP! (18.2435s+0.0002s)
2^168540-4449 is 3-PRP! (14.7559s+0.0002s)
2^180102-4475 is 3-PRP! (18.2889s+0.0001s)
2^186840-4475 is 3-PRP! (19.0133s+0.0001s)
2^191640-4475 is 3-PRP! (19.7276s+0.0001s)

To be completed...