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The 100th term of 1, 7, 13, 19, … is

User Avisra
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1 Answer

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Consider \: the \: sequence \: u_(n) \\ u_(n) \: appears \: to \: be \: arithmtic

Quick Proof:


u_(4)-u_(3)=u_(3)-u_(2)=... \\ 19 - 13 = 13 - 7 = .. \\ 6 = 6 = ...


u_(n) \: is \: arithmetic \: with \: d = 6 \:and \: u_(1) = 1 \\


u_(n) = u_(1)+(n-1)d \\ u_(100) = 1 + (100 - 1)6 \\ u_(100) = 595

User Witold Kowelski
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