求解数列推理1)2,3/2,10/9,7/8,18/25,A.5/14B.11/18C.13/27D.26/492)2,4,6,9,13,19,A.28B.29C.30D.313)-2,1/2,4,2,16,A.32B.64C.128D.2564)21,28,33,42,43,60,A.45B.56C.75D.925)1,3,0,6,10,9,A.13B.14C.15D.17额最好有算法

Question

求解数列推理
1) 2,3/2,10/9,7/8,18/25,A.5/14 B.11/18 C.13/27 D.26/49
2)2,4,6,9,13,19,A.28 B.29 C.30 D.31
3)-2,1/2,4,2,16,A.32 B.64 C.128 D.256
4)21,28,33,42,43,60,A.45 B.56 C.75 D.92
5)1,3,0,6,10,9,A.13 B.14 C.15 D.17
额 最好有算法

Answer 1

(1).2/1,6/4,10/9,14/16,18/25,B(22/36).
(2).2,4,2+4-0,4+6-1,6+9-2,9+13-3,13+19-4(A)
(3).-2,(1/2)^(-2),4^(1/2),2^4,16^2(D)
(4).21,28,33,42,43,60,(45)
7,5,9,1,17,(-15) (后面每两项之和=前一项的2倍)
(5).暂时不懂.