Congratulations to the Great Internet Mersenne Prime Search, who today released their latest Mersenne Prime discovery, M77232917.
I have already found a factor of (M+2)77232917 (using 2kp trial-factoring algorithm) :
James-Wanlesss-iMac:gmp-tf james$ time ./mpptf16.gmp* -P77232917 -S1 -T1000000000000
22404289 3460697185562027
...
James-Wanlesss-iMac:~ james$ time (echo '3460697185562027' | bc | tr -d '\\\n' ; echo) | ~/math/gmp-ecpp/atkin249.gmp-5.0.1.intelOSX.64.static -q
random seed = 1515131256
error_shift = 1000
precision = 10000
Bmax = 2000
Dmax = 20
D = -8, dT = 1, T = 1 -8000
j = 8000
N[0] = 3460697185562027
a = 670951495159981
b = 706264731747355
m = 3460697234137602
q = 239551547
P1 = (0, 1)
P2 = (983431483583515, 2951612507807907)
proven prime
real 0m17.104s
user 0m6.681s
sys 0m0.069s