docs: @Reference(title = "Fast and accurate computation of binomial probabilities", //
        authors = "C. Loader", booktitle = "", //
        url = "http://projects.scipy.org/scipy/raw-attachment/ticket/620/loader2000Fast.pdf", //
        bibkey = "web/Loader00")
    private static double devianceTerm(double x, double np) {
      if(Math.abs(x - np) < 0.1 * (x + np)) {
        final double v = (x - np) / (x + np);
  
        double s = (x - np) * v;
        double ej = 2.0d * x * v;
        for(int j = 1;; j++) {
          ej *= v * v;
          final double s1 = s + ej / (2 * j + 1);
          if(s1 == s) {
            return s1;
          }
          s = s1;
        }
      }
      return x * FastMath.log(x / np) + np - x;
    }