Write a TCL program to get the numbers in the range (given in arguments) which are only divisible by 3 and 7.

Sure, here is a simple TCL program that will print the numbers in a given range that are divisible by both 3 and 7.

proc divisible_by_3_and_7 {start end} {
    for {set i $start} {$i <= $end} {incr i} {
        if {$i % 3 == 0 && $i % 7 == 0} {
            puts $i
        }
    }
}

# Call the function with the range you want to check
divisible_by_3_and_7 1 100

This program defines a procedure divisible_by_3_and_7 that takes two arguments: the start and end of the range to check. It then uses a for loop to iterate over each number in that range. If the current number is divisible by both 3 and 7 (i.e., the remainder when the number is divided by 3 or 7 is 0), it prints the number. Finally, it calls the procedure with the range 1 to 100. You can replace these numbers with any range you want to check.