Single
Double (or Couple)
Triple
Quadruple
Quintuple
Sextuple [no sniggering, please]
Septuple
Octuple
Nonuple
Decuple
Undecuple
Duodecuple
Tredecuple
You see we're just counting by Latin prefixes and when we pass
ten, saying "One-ten," "Two-ten," "Three-ten" and so on.