In the sequence of numbers 4,7,-7,....., the first term is 4. Each even numbered term is 3 more than the previous term.Each odd numbered term after the first is -1 times the previous term. What is the sum of the first 22 terms?

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In the sequence of numbers 4,7,-7,....., the first term is 4. Each even numbered term is 3 more than the previous term.Each odd numbered term after the first is -1 times the previous term. What is the sum of the first 22 terms?

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