code: def find_rosser_block_zero(ctx, n):
      """for n<400 000 000 determines a block were one find our zero"""
      for k in range(len(_ROSSER_EXCEPTIONS) // 2):
          a = _ROSSER_EXCEPTIONS[2 * k][0]
          b = _ROSSER_EXCEPTIONS[2 * k][1]
          if (a <= n - 2) and (n - 1 <= b):
              t0 = ctx.grampoint(a)
              t1 = ctx.grampoint(b)
              v0 = ctx._fp.siegelz(t0)
              v1 = ctx._fp.siegelz(t1)
              my_zero_number = n - a - 1
              zero_number_block = b - a
              pattern = _ROSSER_EXCEPTIONS[2 * k + 1]
              return (my_zero_number, [a, b], [t0, t1], [v0, v1])
      k = n - 2
      t, v, b = compute_triple_tvb(ctx, k)
      T = [t]
      V = [v]
      while b < 0:
          k -= 1
          t, v, b = compute_triple_tvb(ctx, k)
          T.insert(0, t)
          V.insert(0, v)
      my_zero_number = n - k - 1
      m = n - 1
      t, v, b = compute_triple_tvb(ctx, m)
      T.append(t)
      V.append(v)
      while b < 0:
          m += 1
          t, v, b = compute_triple_tvb(ctx, m)
          T.append(t)
          V.append(v)
      return (my_zero_number, [k, m], T, V)
  
file_path: catboost/contrib/python/mpmath/py3/mpmath/functions/zetazeros.py
imports: from .functions import defun, defun_wrapped
label_desc: Use image node_id 1 for calling a global function with example usage: find_rosser_block_zero(ctx, n) and returns: my_zero_number,  list,  T,  V, my_zero_number,  list,  list,  list