Infinite sequence

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Infinite sequence

by II » Sun Feb 17, 2008 1:52 pm
Hi All,

Any ideas on how best to approach this problem.

Thanks,
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by subbu123 » Sun Feb 17, 2008 2:46 pm
Sum of first 4 terms is 6. After every 4 terms, terms repeat.

There are 20 4 terms in 83 tems
sum = 20*6 = 120 + sum of the first three (8) = 128.