What is the sum of the first 28 terms in the following sequence? 1, 1, 2, 1, 3, 2, 1, 4, 3, 2, 1, 5, 4, 3, 2 ...
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A hard CSAT / General Aptitude multiple-choice question from UPSC Prelims 2024. Attempt it above, then check the correct answer and detailed explanation below.
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Correct answer: B. 84
The sequence repeats in decreasing order for each natural number. The sum is calculated as 1 + 2 + 3 + ... + 7 + (7 + 6 + 5 + ... + 1) = 84.
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