Answer:
The program in Python is as follows:
n = int(input("Enter an integer: "))
if n < 0:
    n = 0
print("Sequence:",end=" ")
for i in range(n,-1,-1):
    if i%2 == 0:
        print(i,end = " ")
Explanation:
This gets input for n
n = int(input("Enter an integer: "))
This sets n to 0 if n is negative
<em>if n < 0:</em>
<em>    n = 0</em>
This prints the string "Sequence"
print("Sequence:",end=" ")
This iterates from n to 0
for i in range(n,-1,-1):
This check if current iteration value is even
    if i%2 == 0:
If yes, the number is printed
        print(i,end = " ")