In the previous article, we have discussed Python Program to Find Sum of Series 1-2+3-4+5…+N
Given a number N and the task is to find the triangular number series (1 3 6 10 15 …N) until the given number.
int() function in Python:
The int() function is used to transform a value into an integer number.
Examples:
Example1:
Input:
Given Number = 8
Output:
The Triangular series until the given number{ 8 } is :
1 3 6 10 15 21 28 36
Example2:
Input:
Given Number = 15
Output:
The Triangular series until the given number{ 15 } is :
1 3 6 10 15 21 28 36 45 55 66 78 91 105 120
Program to Print Triangular Number series 1 3 6 10 15 …N in Python
Below are the ways to find the triangular number series (1 3 6 10 15 …N) until the given number N :
Method #1: Using While Loop (Static Input)
Approach:
- Give the number N as static input and store it in a variable.
- Take a variable say k and initialize its value with 1.
- Loop until the value of k is less than or equal to the given number using the while loop.
- Inside the loop, multiply the value of k with k+1 and divide the result by 2 and convert it into an integer using the int() function.
- Store it in a variable say p.
- Print the above result (p) separated by spaces to get the triangular series until the given number.
- Increment the value of k by 1 and store it in the same variable k.
- The Exit of the Program.
Below is the implementation:
# Give the number N as static input and store it in a variable.
gvn_numb = 8
# Take a variable say k and initialize its value with 1.
k = 1
print("The Triangular series until the given number{", gvn_numb, "} is :")
# Loop until the value of k is less than or equal to the given number using the while loop.
while(k <= gvn_numb):
# Inside the loop, multiply the value of k with k+1 and divide the result by 2 and
# convert it into an integer using the int() function.
# Store it in a variable say p.
p = int((k*(k+1))/2)
# Print the above result (p) separated by spaces to get the triangular series until
# the given number.
print(p, end=" ")
# Increment the value of k by 1 and store it in the same variable k.
k += 1
Output:
The Triangular series until the given number{ 8 } is :
1 3 6 10 15 21 28 36
Method #2: Using While loop (User Input)
Approach:
- Give the number N as user input using the int(input()) function and store it in a variable.
- Take a variable say k and initialize its value with 1.
- Loop until the value of k is less than or equal to the given number using the while loop.
- Inside the loop, multiply the value of k with k+1 and divide the result by 2 and convert it into an integer using the int() function.
- Store it in a variable say p.
- Print the above result (p) separated by spaces to get the triangular series until the given number.
- Increment the value of k by 1 and store it in the same variable k.
- The Exit of the Program.
Below is the implementation:
# Give the number N as user input using the int(input()) function and
# store it in a variable.
gvn_numb = int(input("Enter some Random Number = "))
# Take a variable say k and initialize its value with 1.
k = 1
print("The Triangular series until the given number{", gvn_numb, "} is :")
# Loop until the value of k is less than or equal to the given number using the while loop.
while(k <= gvn_numb):
# Inside the loop, multiply the value of k with k+1 and divide the result by 2 and
# convert it into an integer using the int() function.
# Store it in a variable say p.
p = int((k*(k+1))/2)
# Print the above result (p) separated by spaces to get the triangular series until
# the given number.
print(p, end=" ")
# Increment the value of k by 1 and store it in the same variable k.
k += 1
Output:
Enter some Random Number = 15
The Triangular series until the given number{ 15 } is :
1 3 6 10 15 21 28 36 45 55 66 78 91 105 120
If you wanna write simple python programs as a part of your coding practice refer to numerous Simple Python Program Examples existing and learn the approach used.