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Question
Choose the correct alternative:
The nth term of the sequence 1, 2, 4, 7, 11, …… is
Options
n2 + 3n2 + 2n
n3 – 3n2 + 3n
`("n"("n" + 1)("n" + 2))/3`
`("n"^2 - "n" + 2)/2`
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Solution
`("n"^2 - "n" + 2)/2`
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