docs: function coeffToString(a) {
          var s, z,
              i = 1,
              j = a.length,
              r = a[0] + '';
  
          for ( ; i < j; ) {
              s = a[i++] + '';
              z = LOG_BASE - s.length;
              for ( ; z--; s = '0' + s );
              r += s;
          }
  
          // Determine trailing zeros.
          for ( j = r.length; r.charCodeAt(--j) === 48; );
          return r.slice( 0, j + 1 || 1 );
      }