निम्नलिखित अक्षर-समूह श्रृंखला में लुप्त पद ज्ञात कीजिए: SAG26, VGP29, YMY35, ?, EYQ56

Which number will replace the question mark (?) in the following series? 83, 79, 71, 67, 59, 55, ?

Which of the following letter-number clusters will replace the question mark (?) in the given series to make it logically complete? HLE23, JJH21, LHK19, NFN17, ?