Clarify that the default Unix shell is found through PATH

README.md

@@ -89,7 +89,7 @@ hyperfine -L compiler gcc,clang '{compiler} -O2 main.cpp'
 
 ### Intermediate shell
 
-By default, commands are executed using a predefined shell (`/bin/sh` on Unix, `cmd.exe` on Windows).
+By default, commands are executed using `sh` on Unix (resolved through `PATH`) or `cmd.exe` on Windows.
 If you want to use a different shell, you can use the `-S, --shell <SHELL>` option:
 ```sh
 hyperfine --shell zsh 'for i in {1..10000}; do echo test; done'

doc/hyperfine.1

@@ -153,7 +153,7 @@ arithmetics.
 .RS
 Example:
 .RS
-\fBhyperfine\fR \fB\-P\fR size 0 3 'sleep $((1 << {size}))'
+\fBhyperfine\fR \fB\-P\fR size 0 3 'sleep $((2**{size}))'
 .RE
 .RE
 .IP

src/cli.rs

@@ -164,7 +164,7 @@ fn build_command() -> Command {
                      Example:  hyperfine -P threads 1 8 'make -j {threads}'\n\n\
                      This performs benchmarks for 'make -j 1', 'make -j 2', …, 'make -j 8'.\n\n\
                      To have the value increase following different patterns, use shell arithmetics.\n\n  \
-                     Example: hyperfine -P size 0 3 'sleep $((1 << {size}))'\n\n\
+                     Example: hyperfine -P size 0 3 'sleep $((2**{size}))'\n\n\
                      This performs benchmarks with power of 2 increases: 'sleep 1', 'sleep 2', 'sleep 4', …\n\
                      The exact syntax may vary depending on your shell and OS."
                 ),