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The sequence $k_n$ is defined by $k_1 = 19$, $k_2 = 11$ and $k_{n+2} = k_n + k_{n+1}$ for $n \ge 1$. How many of the first 2025 terms in the sequence are even?

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Source: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty, ordering) added by this project. Solutions are the publisher's, linked not copied.