Difficulty: Medium
Correct Answer: 32
Explanation:
Introduction / Context:
This is a wrong-term detection problem in a number series. We must discover a single, clean rule that fits all positions except one, and then mark the violating term.
Given Data / Assumptions:
Concept / Approach:
A compact pattern that nearly fits is: a(n+1) = a(n) * (n+1) + (n+1)^2. We verify each transition and isolate any mismatch.
Step-by-Step Solution:
Verification / Alternative check:
If the 3rd term were 33 instead of 32, then 33*4 + 16 = 148 (exact). Thus a single earlier slip (32 vs 33) explains both mismatches and restores a perfect rule for the tail.
Why Other Options Are Wrong:
Terms 8, 148, 765 all become consistent once the 3rd term is corrected from 32→33; they are not the primary error.
Common Pitfalls:
Blaming a later term when an earlier off-by-one causes downstream wobble. Always check if fixing one term repairs later transitions.
Final Answer:
32 is the lone wrong term under a(n+1) = a(n)*(n+1) + (n+1)^2.
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