diff --git a/sys/man/1/pc b/sys/man/1/pc
index e4e11792b..e85298fba 100644
--- a/sys/man/1/pc
+++ b/sys/man/1/pc
@@ -51,7 +51,7 @@ Numbers can use the prefixes
 .B _
 in numbers can be added for readability and is ignored.
 .SS Builtin functions
-.TF xtend(n,m)
+.TF \fIcat(a0,n0,...,aN,nN)
 .TP
 .I bin(n)
 Display \fIn\fR in binary.
@@ -93,8 +93,8 @@ The minimum number of bits required to represent \fIn\fR as an unsigned number.
 .I sbits(n)
 The minimum number of bits required to represent \fIn\fR as an signed number.
 .TP
-.I cat(a0,n0,...,aN,nN)
-Truncate each of the \fIa\fR arguments to \fIn\fR bits and concatenate their binary representation.
+.I cat(a\d\s70\s10\u,n\d\s70\s10\u,...,a\d\s7N\s10\u,n\d\s7N\s10\u)
+Truncate each of the \fIa\d\s7i\s10\u\fR arguments to \fIn\d\s7i\s10\u\fR bits and concatenate their binary representation.
 .TP
 .I gcd(n,m)
 The greatest common divisor of \fIn\fR and \fIm\fR.