Question

The Fibonacci sequence 1, 1, 2, 3, 5, 8, 13, 21…… starts with two 1s, and each term afterward is the sum of its two predecessors. Please write a function, Fib(n), which takes n as the input parameter. It will return the n-th number in the Fibonacci sequence. Using R, the output for Fib(9) should give only the 9th element in the sequence and not any of the previous elements. Please Help :)

Answer 1

SOURCE CODE: in R language

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**Please look at the Screenshot below and use this code to copy-paste.

***The code in the below screenshot is neatly indented for better understanding.
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Fib <- function(nterms)

{

# first two terms

n1 = 1

n2 = 1

count = 2

while(count < nterms)

{

# Calculate the sum of last two numbers

nth = n1 + n2

# update values

n1 = n2

n2 = nth

count = count + 1

}

# Return the nth fibonacci number

return (nth)

}

# test the function here with different values

print(Fib(5))

print(Fib(7))

print(Fib(10))

print(Fib(15))

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