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IKMC 2020 - Grades 11-12 - Set 2 - Self-study Question 18

IKMC · IKMC 2020 - Grades 11-12 - Set 2 - Self-study

Question 18

The sequence has $f_1=1$, $f_2=3$, and $f_{n+2}=f_n+f_{n+1}$ for $n\ge1$. How many of its first 2020 terms are even?
  1. 673
  2. 674
  3. 1010
  4. 1011
  5. 1347