填空并写出数列的通项公式1,3,7,,31,,127;2,5,,17,26,,50;1/2,-1/4,,-1/16,1/32,,1/128;1,√2,,2,√5,,√7

Question

填空并写出数列的通项公式
1,3,7,,31,,127;
2,5,,17,26,,50;
1/2,-1/4,,-1/16,1/32,,1/128;
1,√2,,2,√5,,√7

Answer 1

15 63 2·2^(n-1)-1
10 37 n²+1
1/8 -1/64 (-1)^(n+1)1/(2^n)
√3 √6 √n
以上n=1,2,3,.