C Program to Find Sum of series 1²+2²+3²+….+n²

Program to find sum of series 1²+2²+3²+….+n² in C; Through this tutorial, we will learn how to find sum of series 1²+2²+3²+….+n² using a standard formula, for loop, function, and recursion in c programs.

Programs to Find Sum of series 1²+2²+3²+….+n² in C

Let’s ise the following programs to find/evaluate the series 1^2+2^2+3^2+……+n^2 in c using for loop, standard formula, function and recursion:

• C Program to Find Sum of series 1²+2²+3²+….+n² using Standard Formula
• C Program to Find Sum of series 1²+2²+3²+….+n² using For Loop
• C Program to Find Sum of series 1²+2²+3²+….+n² using Function
• C Program to Find Sum of series 1²+2²+3²+….+n² using Recursion

C Program to Find Sum of series 1²+2²+3²+….+n² using Standard Formula

/* C Program to Calculate Sum of series 1²+2²+3²+....+n² */
#include <stdio.h>

int main()
{
  int Number, Sum = 0;

  printf("\n Please Enter any positive integer \n");
  scanf(" %d",&Number);

  Sum = (Number * (Number + 1) * (2 * Number + 1 )) / 6;

  printf("\n The Sum of Series for %d = %d ",Number, Sum);

}

The output of above c program; is as follows:

Please Enter any positive integer
10
The Sum of Series for 10 = 385 

C Program to Find Sum of series 1²+2²+3²+….+n² using For Loop

#include <stdio.h>

int main()
{
  int Number, i, Sum = 0;

  printf("\nPlease Enter any positive integer \n");
  scanf("%d",&Number);

  Sum = (Number * (Number + 1) * (2 * Number + 1 )) / 6;

  for(i =1; i<=Number;i++)
  {
    if (i != Number)
       printf("%d^2 + ",i);

    else
       printf("%d^2 = %d ",i, Sum);
  }
}

The output of above c program; is as follows:

Please Enter any positive integer
10
1^2 + 2^2 + 3^2 + 4^2 + 5^2 + 6^2 + 7^2 + 8^2 + 9^2 + 10^2 = 385 

C Program to Find Sum of series 1²+2²+3²+….+n² using Function

#include <stdio.h>

void Sum_Of_Series(int);

int main()
{
  int Number;

  printf("\n Please Enter any positive integer \n");
  scanf("%d",&Number);

  Sum_Of_Series(Number);
}

void Sum_Of_Series(int Number)
{
  int i, Sum;
  Sum = (Number * (Number + 1) * (2 * Number + 1 )) / 6;

  for(i =1;i<=Number;i++)
  {
   if (i != Number)
     printf("%d^2 + ",i);
   else
     printf(" %d^2 = %d ", i, Sum);
  }
}

The output of above c program; is as follows:

Please Enter any positive integer
5
1^2 + 2^2 + 3^2 + 4^2 +  5^2 = 55 

C Program to Find Sum of series 1²+2²+3²+….+n² using Recursion

#include <stdio.h>

int Sum_Of_Series(int);

int main()
{
  int Number, Sum;

  printf("\nPlease Enter any positive integer \n");
  scanf("%d",&Number);

  Sum=Sum_Of_Series(Number);

  printf("\nSum of the Series  = %d",Sum);
}

int Sum_Of_Series(int Number)
{
  if(Number == 0)
    return 0;

  else
    return (Number*Number) + Sum_Of_Series(Number-1);
}

The output of above c program; is as follows:

Please Enter any positive integer
5
Sum of the Series  = 55

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