1
/-------T-------\ 1 TPRSL / | \ 2 SDCBA
/ /---S---\ \ 3 TSAEL
/ / 2 \ \ 4 TPHDS
/ 3 A---B---C---D 4 \ 5 ABFIE
/ / 5 / \ 6 \ \ 6 CDHKG
/ E F 7 G H \ 7 BCGJF
/ / \ / \ / \ / \ \ 8 ETMQL
\ / I \ / K \ / 9 FIJNM
\ | | \ / | | / 10 GKONJ
\ | 8 | 9 J 10 | 11 | / 11 HPROK
\| | | | |/ 12 NORQM
L M-----N-----O P
\ \ / /
\ \ 12 / /
\--- Q-----R----/
Figure 1
Every face in Figure 1 has 5 sides. This is necessary to assure that all
the vertices in the 'triangulation' dual have degree > 4.
To expand Figure 1, it is necessary to add 2 vertices, 3 edges and 1 face
Actually some existing edges will need to be removed to accommodate the
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