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Fibonacci Sequence

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You can calculate a number in the Fibonacci sequence using recursion.

Following the math theory of F(n) = F(n-2) + F(n-1), for any i > 0, 

// Returns the i'th Fibonacci number
public int fib(int i) {
    if(i <= 2) {
        // Base case of the recursive function.
        // i is either 1 or 2, whose associated Fibonacci sequence numbers are 1 and 1.
        return 1;
    }
    // Recursive case. Return the sum of the two previous Fibonacci numbers.
    // This works because the definition of the Fibonacci sequence specifies
    // that the sum of two adjacent elements equals the next element.
    return  fib(i - 2) + fib(i - 1);
    
}

fib(10); // Returns 55
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Recursion:
* Recursion
* Recursion in plain English
* Fibonacci Sequence
* Using Recursion to Get Directory Tree
* Recursively describe an object structure
* PowerOf calculation
* Factorial calculation
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0 Getting Started With C#
1 Literals
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4 Equality Operator
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