Chapter #6 – Flow of Control

Class 11 – Chapter 6 Solutions – PROGRAMMING EXERCISES #5
Write a program to generate the sequence: –5, 10, –15, 20, –25….. upto n, where n is an integer input by the user.
Python Program:
def generate_sequence(n):
sequence = []
for i in range(1, n + 1):
# Calculate the term based on the index
term = (-1) ** i * (5 * i)
sequence.append(term)
return sequence
# Get user input
try:
n = int(input("Enter an integer value for n: "))
if n <= 0:
print("Please enter a positive integer.")
else:
result = generate_sequence(n)
print("Generated sequence:", result)
except ValueError:
print("Invalid input. Please enter an integer.")
You can checkout the code from Github here – Programming Exercises – 5
Explanation of the Code:
1. Function Definition: The generate_sequence function takes an integer n as
input and initializes an empty list sequence to store the terms.
2. Loop: It iterates from 1 to n, calculating each term using the formula
(-1) ** i * (5 * i). This formula alternates the sign and multiplies by 5.
3. User Input: The program prompts the user to enter an integer value for n.
It checks if the input is valid and positive.
4. Output: If valid, it calls the function and prints the generated sequence.
Example Output:
Enter an integer value for n: 10
Generated sequence: [-5, 10, -15, 20, -25, 30, -35, 40, -45, 50]
NCERT Computer Science Class 11 Chapter 6 Solutions – Q 10
NCERT Computer Science Class 11 Chapter 6 Solutions – Q 10