- Oh no, another one...
I have found the largest known CPAP-8 at 112 digits:
10097274767216*250# + x + 210n, for n=0..7
where x is the 99-digit constant:
The GMP library was used for prp testing and Tony Forbes' VFYPR proved the
The choice of x means that 1408 of the 209*7 = 1463 intermediate numbers are
guaranteed to have a factor below 250.
The expected time was 13 days but with amazing luck again, it only took 14
It was almost completely unbelievable luck: 30 seconds into a short test run,
an AP-8 popped out with multiplier c=1000018345123. It was the first AP-4 and
there was a single intermediate prime c*250# + x + 666. Beastly!
The CPAP record page has been updated less than a day after the opening with
this and 3 additional CPAP-7:
Jens Kruse Andersen