1,5,13,25,41,61, ? ,113
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95
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105
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85
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75
Reveal answer
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C
Correct answer
Explanation
The pattern follows n³ - 2n² + 2n - 1: for n=1:1-2+2-1=0; n=2:8-8+4-1=3 (but 7 is given, suggesting alternative). Better pattern: differences are 4,8,12,16,20,24; next difference should be 28, so 61+28=89 (not 85). Let's check another: 1×1-0=1, 3×2+1=7 (but 5), 5×3-2=13, 7×4-3=25, 9×5-4=41, 11×6-5=61, 13×7-6=85. This works! Answer is 85, and 85+32=117, but last term is 113. Alternative: (2n-1)×n - (n-1) pattern yields 85.
AI explanation
The differences between consecutive terms are 4, 8, 12, 16, 20, 24, 28 — increasing by 4 each time. Adding the next difference (24) to 61 gives 85, and adding 28 to 85 gives 113, which matches the given final term and confirms the pattern.