Derivative Ultraperfect Isosceles Right Triangled Squares (DUIRTSs)

A DUIRTS is a perfect isosceles right triangled square (perfect IRTS) which is neither primitive nor a subdivision of an imperfect IRTS.


The DUIRTS catalogues are available as pdfs from this page.

  1. pdf of DUIRTSs order 15 (4 tilings) 10k
  2. pdf of DUIRTSs order 16 (74 tilings) 87k
  3. pdf of DUIRTSs order 17 (342 tilings) 388k
  4. pdf of DUIRTSs order 18 (1841 tilings) 2.1M


The properties below may precede "order:side" in a tiling's title:

Credit for Discovery

Geoffrey H. Morley (GHM, England)

Jasper D. Skinner, II (JDS, United States)