SHELL

cat with line numbers

cat -n text.txt

cat to line number

$ cat -n file | awk '$1>=4 && $1<=8 || $1==12 || $1==42'
 4  Line 4
 5  Line 5
 6  Line 6
 7  Line 7
 8  Line 8
12  Line 12
42  Line 42

cat to line number

awk 'NR==1' file.txt