Sindbad~EG File Manager

Length of proof is 9.  Level of proof is 4.
 
---------------- PROOF ----------------
 
14 [] -E(xa,xb,xc,xd)|E(xc,xd,xa,xb).
24 [] T(xa,xb,xb).
25 [] -T(xa,xb,xc)|T(xc,xb,xa).
27 [] -T(xa,xb,xc)| -T(xb,xa,xc)|xa=xb.
52 [] Col(xa,xb,xa).
74 [] -T(xa,xb,xc)| -E(xa,xc,xa,xb)|xc=xb.
86 [] sameside(xa,xp,xb)| -Col(xa,xp,xb)|T(xa,xp,xb).
145 [] -Col(xa,xb,xc)|T(xa,xb,xc)|T(xb,xc,xa)|T(xc,xa,xb).
158 [] -sameside(xa,xp,xb)|xb!=xp.
164 [] -T(xa,xm,xb)| -E(xm,xa,xm,xb)|M(xa,xm,xb).
173 [] Col(a,m,b).
174 [] E(m,a,m,b).
175 [] a!=b.
176 [] -M(a,m,b).
177 [binary,173.1,145.1] T(a,m,b)|T(m,b,a)|T(b,a,m).
213 [binary,174.1,164.2,unit_del,176] -T(a,m,b).
221 [binary,174.1,74.2,unit_del,175] -T(m,b,a).
246 [binary,174.1,14.1] E(m,b,m,a).
380 [ur,27,24,175] -T(b,a,b).
463 [binary,177.3,25.1,unit_del,213,221] T(m,a,b).
885 [binary,380.1,86.3,unit_del,52] sameside(b,a,b).
1113 [binary,463.1,74.1,unit_del,246] b=a.
1267 [binary,1113.1,158.2] -sameside(x,a,b).
1268 [binary,1267.1,885.1] $F.