23n - 7n - 1 is divisible by
64
36
49
25
The sum of the rational terms in the expansion of is
41
32
18
9
The total number of terms in the expansion of (x+y)100 +(x-y)100 after simplification is
51
202
100
50
The number of positive odd divisors of 216 is
4
6
8
12
The coefficient of x in the expansion of (1+x)(1+2x)(1+3x)...(1+100x) is
5050
10100
5151
4950
, then r is
5
3
2
The coefficient of xn in the expansion of (1+2x+3x2 +...) is
0
-1
1
The coefficient of x-7 in the expansion of will be
The total number of terms in the expansion of (x+y)100 + (x-y)100 after simplification is
The ninth term of the expansion is