I wrote https://github.com/sethtroisi/goldbach in the last four hours and I think it's 10-100x faster than your code
time ./goldbach -t8 -K 1024 -e 100''000''000''000 real 0m44.133s user 3m32.193s sys 0m0.092s time ./goldbach -t12 -K 1500 -e 1''000''000''000''000 267468893942 = 267468891139 + 2803 (407) 926868341768 = 926868338701 + 3067 (437) 599533546358 = 599533542901 + 3457 (481) real 2m3.909s user 16m0.729s sys 0m37.960s
I wouldn't trust it 100% but it finds all terms in https://oeis.org/A025018 and https://oeis.org/A025019 and I can verify in https://sweet.ua.pt/tos/goldbach.html
I wrote https://github.com/sethtroisi/goldbach in the last four hours and I think it's 10-100x faster than your code
I know of at least another 4x I could improve it but I've been nerd sniped enough for the night.I wouldn't trust it 100% but it finds all terms in https://oeis.org/A025018 and https://oeis.org/A025019 and I can verify in https://sweet.ua.pt/tos/goldbach.html