(2n-1)(2n)(2n-2)... 2 -

(2n-1)... (2n);(6)13 ... (2n-1)(2n)(2n-2)... 2.2.按自然数从小到大为标准次序，求下列排列的逆序数：(1)1234

(2n-1)24 ... (2n); (6)13 ... (2n-1)(2n)(2n-2) ... 2.2.按自然数从小到大为标准次序，求下列各排列的逆序数：

(2n-1)24... (2n);（6）13... (2n-1)(2n)(2n-2)... 2.按自然数从小到大为标准次序，求下列排列的逆序数：（1）1234;

321;-|||-(4) ... (2n-1)(2n)(2n-2)... 642

(2n-1)(2n)(2n-2)... 2;-|||-(4) (n-1)... 1.

(2n-1)24... (2n)B 3421 C 2413... (2n-1)24... (2n)哪个是偶排列?B3421C2413

(2n-1)246... (2n)求下列全排列的逆序数。（1）634521（2）53142（3）54321（4）

,求幂级数 sum _(n=1)^infty dfrac (2n-1)({2)^n}(x)^2n-2 的和函数,并求级数 sum _(n=1)^infty df

(2n-1)24... (2n);-|||-(6) ... (2n-1)(2n)(2n-2)... 2.-|||-3.写出四阶行列式中含有因子a11a 23的项

(2n-1)24... (2n) ;-|||-(6) ... (2n-1)(2n)(2n-2)... 2.-|||-3.写出四阶行列式中含有因子a11a23的项