64-bit VM: rjt 0.903s Laurent + updates 0.696s iM71 + updates 0.602s Step counting in C 0.273s (1st time involves compiling) AMD 3970x: rjt 0.635s Laurent + updates 0.516s iM71 + updates 0.467s Step counting in C 0.191s (1st time involves compiling) Collatz(837799) has sequence length of 525 steps Collatz(626331) has sequence length of 509 steps Collatz(939497) has sequence length of 507 steps Collatz(704623) has sequence length of 504 steps Collatz(910107) has sequence length of 476 steps Collatz(927003) has sequence length of 476 steps Collatz(511935) has sequence length of 470 steps Collatz(767903) has sequence length of 468 steps Collatz(796095) has sequence length of 468 steps Collatz(970599) has sequence length of 458 steps Collatz(546681) has sequence length of 452 steps Collatz(818943) has sequence length of 450 steps Collatz(820022) has sequence length of 450 steps Collatz(820023) has sequence length of 450 steps Collatz(410011) has sequence length of 449 steps Collatz(615017) has sequence length of 447 steps Collatz(886953) has sequence length of 445 steps Collatz(906175) has sequence length of 445 steps Collatz(922524) has sequence length of 445 steps Collatz(922525) has sequence length of 445 steps