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1. Count Digits in a Number2. Reverse a Number3. Check Palindrome Number4. Sum of Digits5. Armstrong Number Check6. Perfect Number Check7. Print Primes Between 1-1008. Check if Number is Prime9. Fibonacci Series Up to N10. Sum of First N Fibonacci Terms11. Product of Digits12. Strong Number Check13. Harshad Number Check14. Abundant Number Check

Sum of First N Fibonacci Terms

Calculate sum of first n Fibonacci terms.

IntermediatePhase 2 - Level 2: Number-based Looping LogicExample 10 of 14
sum-of-first-n-fibonacci-terms.py
1# Take n
2n = int(input("Enter n: "))
3

4# Calculate sum
5if n <= 0:
6    sum_fib = 0
7elif n == 1:
8    sum_fib = 0
9elif n == 2:
10    sum_fib = 1
11else:
12    a, b = 0, 1
13    sum_fib = 1  # 0 + 1
14    for i in range(2, n):
15        c = a + b
16        sum_fib += c
17        a, b = b, c
18

19print(f"Sum of first {n} Fibonacci terms: {sum_fib}")

Output

Enter n: 5
Sum of first 5 Fibonacci terms: 7

What's going on

Generate Fibonacci terms and accumulate sum.

Key Concepts:

Generate Fibonacci sequence
Add each term to sum
Handle edge cases (n <= 2)

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