((p p q) (p p q))
(((C1 -> C2) (C2 -> C3) (C2 C3)) (C1 0))
y1y2(((y1 = y2) (xRy1) (y1Ry2)) z1((xRz1) -> z2(z1Rz2)))
# - -
@ - -
#' - -1 -
@' - -1 -
[n] -
<n> -
[n]'-
<n>'-
& - -
| - -
~ - -
-> -
<- -
<-> -