The first question can be changed to An+ 1-An-(An-An_ 1), and the original formula is arithmetic progression with a tolerance of 5.

The second question is also very simple, and it is also a substitution formula, but I can't type the formula and I'm sorry I can't tell you. . . .

You have always simplified the conditions of the second question with formulas, and then divided the 2N power of -2 on the left by the right to get the 1 quiz answer of the second question. I can't say the rest, so I can only stop here.