Write a c program to find out the sum of series 1^2 + 2^2 + …. + n^2


Levels of difficulty: / perform operation:

Mathematical Formula:

Sum of the series 12 + 22 + 32 + … + n2 = n (n+1) (2n+1)/6

C Program

#include<stdio.h>
int main() {
	int n,i;
	int sum=0;
	printf("Enter the n i.e. max values of series: ");
	scanf("%d",&n);
	sum = (n * (n + 1) * (2 * n + 1 )) / 6;
	printf("Sum of the series : ");
	for (i =1;i<=n;i++) {
		if (i != n)
		             printf("%d^2 + ",i); else
		             printf("%d^2 = %d ",i,sum);
	}
	return 0;
}

Output:

Enter the n i.e. max values of series: 5
Sum of the series: 1^2 + 2^2 + 3^2 + 4^2 + 5^2 = 55