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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 <h1 align="center">Advanced Loops</h1>
<h2>01. Numbers 1...N with Step 3</h2>
Problem
Step1:  <h2>02. Numbers N...1</h2>
Problem
Step2:  <h2>03. Powers of Two</h2>
Problem
Step3:  <h2>04. Even Powers of 2</h2>
Problem
Step4:  <h2>05. Sequence 2k+1</h2>
Problem
Step5:  <h2>06.Number in Range [1...100]</h2>
Problem
Step6:  <h2>07.Greatest Common Divisor (CGD)</h2>
Problem
Step7:  <h2>08.Factorial</h2>
Problem
Step8:  <h2>09. Sum Digits</h2>
Problem
Step9:  <h2>10.Check Prime</h2>
Problem
Step10:  <h2>11.Enter Even Number</h2>
Problem
Step11:  <h2>12.Fibonacci</h2>
Problem
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Python Code:
n = int(input())
for i in range(1,n + 1, 3):
    print(i)
Explanation: <h1 align="center">Advanced Loops</h1>
<h2>01. Numbers 1...N with Step 3</h2>
Problem:
Write a program that enters a number and prints the numbers from 1 to n through 3 (step
End of explanation
n = int(input())
for i in range(n, 0, -1):
    print(i)
Explanation: <h2>02. Numbers N...1</h2>
Problem:
Write a program that sets a positive integer n and prints the numbers from n to 1 in reverse order (from the largest to the smallest).
End of explanation
n = int(input())
for i in range(0, n + 1, 1):
    print(pow(2,i))
Explanation: <h2>03. Powers of Two</h2>
Problem:
Write a program that reads from the console an integer n and prints the numbers from 1 to 2n.
End of explanation
n = int(input())
for i in range(0, n + 1, 1):
    if i % 2 == 0:
        print(pow(2,i))
Explanation: <h2>04. Even Powers of 2</h2>
Problem:
Write a program that enters n and prints the even degrees at 2 ≤ 2n: 20, 22, 24, 28, ..., 2n.
End of explanation
n = int(input())
result = 1
while result <= n:
    print(result)
    result = result * 2 + 1
Explanation: <h2>05. Sequence 2k+1</h2>
Problem:
Write a program that enters a number n and prints all numbers ≤ n of the row: 1, 3, 7, 15, 31, ....
Each subsequent number is calculated as the previous number * 2 + 1.
End of explanation
n = int(input('Еnter a number in the range [1...100]: '))
while 1 > n or n > 100:
    print("Invalid number!")
    n = int(input('Еnter a number in the range [1...100]: '))
print("The number is: "+ str(n))
Explanation: <h2>06.Number in Range [1...100]</h2>
Problem:
Write a program that introduces a positive integer n in the range [1 ... 100].
When entering a number outside the specified range, an error message is printed and the user is prompted to enter a new number.
End of explanation
a = int(input())
b = int(input())
while b != 0:
    save = a % b
    a = b
    b = save
print(a)
Explanation: <h2>07.Greatest Common Divisor (CGD)</h2>
Problem:
Write a program that introduces two integer positive integers a and b and calculates and prints their largest common divisor (NOD).
End of explanation
n = int(input())
result = 1
for i in range(1, n + 1):
    result *= i
print(result)
Explanation: <h2>08.Factorial</h2>
Problem:
Write a program that enters an integer n (1 ≤ n ≤ 12) and calculates and prints n! = 1 * 2 * ... * n (n factorial).
End of explanation
n = input()
sum = 0
for i in n:
    sum += int(i)
print(sum)
Explanation: <h2>09. Sum Digits</h2>
Problem:
Write a program that enters an integer num and prints the sum of its numbers.
End of explanation
import  math
n = int(input())
is_prime = True
if n < 2:
    print('Not Prime')
else:
    end = int(math.sqrt(n))
    for i in range(2, end + 1):
        if n / i == n//i:
          is_prime = False
if is_prime:
    print('Prime')
else:
    print('Not Prime')
Explanation: <h2>10.Check Prime</h2>
Problem:
Write a program that enters an integer n and checks whether it is a simple number (whether it is divided by itself and per unit).
Print "Prime" or "Not prime".
End of explanation
n = float(input('Enter even number: '))
while n % 2 != 0:
    print('Invalid number!')
    n = int(input('Enter even number: '))
n = print('Even number entered: ' + str(n))
Explanation: <h2>11.Enter Even Number</h2>
Problem:
Write a program that introduces an even number.
If the user has entered the wrong number, a new one must be entered.
End of explanation
n = int(input())
a = 1
b = 2
for i in range(1, n):
    new_b = a + b
    a = b
    b = new_b
print(a)
Explanation: <h2>12.Fibonacci</h2>
Problem:
Write a program that enters an integer and calculates the Fibonacci nth number.
The zero figure of Fibonacci is 1, the first one is also 1, and the next is the sum of the previous two.
End of explanation
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