Differences are multiples of 6 (+6, +12, +18, ...): find the term

The same question, asked 2 times: 19 Jul 2023 S3*, 26 Jul 2023 S1. Every wording below, oldest first.

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Question 1
19 Jul 2023 S3
4 $Which of the following numbers will replace the question mark (?) in the given series? 17, ?, 35, 53, 77, 107$
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Question 2
26 Jul 2023 S1
2 $Which of the following numbers will replace the question mark (?) in the given series? 8, 14, ? , 44, 68, 98, 134$
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