function getcust(cusma, pin) {
  hdr = "../extranet/ecd/" ;
  e = 1 * cusma.substring (4, 5) + 13 ;
  d = 1 * cusma.substring (3, 4) + e + 13 ;
  if (d > 36) { d = d - 36 ; }
  c = 1 * cusma.substring (2, 3) + d + 13 ;
  if (c > 36) { c = c - 36 ; }
  b = 1 * cusma.substring (1, 2) + c + 13 ;
  if (b > 36) { b = b - 36 ; }
  e = e - Math.floor (e/10) * 10 ;
  d = d - Math.floor (d/10) * 10 ;
  c = c - Math.floor (c/10) * 10 ;
  b = b - Math.floor (b/10) * 10 ;

  test = "T" + b + c + d + e ;
  if (test == "T" + pin) {
      alfa = "0ABCDEFGHIJKLMNOPQRSTUVWXYZ" ;
      bno = cusma * 100 + 1000000 ;
      a = Math.floor (bno / 456976) ;
      bno = bno - a * 456976 ;
      b = Math.floor (bno / 17576) ;
      bno = bno - b * 17576 ;
      c = Math.floor (bno / 676) ;
      bno = bno - c * 676 ;
      d = Math.floor (bno / 26) ;
      e = bno - d * 26 ;
      a = alfa.substring (a, a+1) ;
      b = alfa.substring (b, b+1) ;
      c = alfa.substring (c, c+1) ;
      d = alfa.substring (d, d+1) ;
      e = alfa.substring (e, e+1) ;
      window.location = hdr + "CUS" + a + b + c + d + e + ".HTM" ;
}
  else                   {
      window.location = "indexc.htm" ; 
      }
}