Write a program to find the sum of the numbers in the
following series:
1 4 10 19 34 52 73 100 ... N
Example if the value for N is 105, then the sum is 293
Note : Print only the output number. If the sum is 293,
then print only 293
Answers
Answer:
Program to print the series 1, 3, 4, 8, 15, 27, 50… till N terms
Given a number N, the task is to print the first N terms of the following series:
1, 3, 4, 8, 15, 27, 50…
Examples:
Input: N = 7
Output: 1, 3, 4, 8, 15, 27, 50
Input: N = 3
Output: 1, 3, 4
Recommended: Please try your approach on {IDE} first, before moving on to the solution.
Approach: From the given series we can find the formula for Nth term:
1st term = 1, 2nd term = 3, 3rd term = 4
4th term = 1st term + 2nd term + 3rd term
5th term = 2nd term + 3rd term + 4th term
6th term = 3rd term + 4th term + 5th term
.
.
so on
Answer:
#include<iostream>
using namespace std;
int main()
{
int n,count=0;
cin>>n;
int num=1,sum=0;
for(int i=1;num<n;i++)
{
if(i%4!=0)
{
sum+=num;
num=num+3*i;
}
cout<<num<<" ";
}
cout<<sum;
}
Explanation:
As you can see every term increasing by 3 multiple but in every 4th case it is increasing by 6+