code: func New() *MT19937 {
  	res := &MT19937{
  		state: make([]uint64, n),
  		index: notSeeded,
  	}
  	return res
  }
docs: // New allocates a new instance of the 64bit Mersenne Twister.
  // A seed can be set using the .Seed() or .SeedFromSlice() methods.
  // If no seed is set explicitly, a default seed is used instead.