Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 0 and 1, the first 12 terms will be:
0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...
By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.
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"""first few numbers : 0 1 1 2 3 5 8 13..."""
a=1
b=0
c=0
i=0
mylist=[0]
while (a<=4000000):
c=a+b #c is the value of the sum of the previous two terms.
b=a #b then becomes the term that was in front of it, a.
a=c # a then becomes c
if a%2==0: #even
mylist[i]=a
mylist.append(a)
i+=1 #goes to next element on the list
print(mylist) # THIS IS THE LIST OF ALL THE EVEN NUMBERS! not too sure why 3524578 appears twice,
del mylist[11] # so it is deleted here.
print(mylist)
answer = sum(mylist)
print(answer) # The answer is 4613732!
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# This cell will be used for grading, leave it at the end of the notebook.
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