=3!2!
特别地,当xn为1,2,3,4,...时,
|D| = 2!3!4!...
计算$$\left |\begin{array}{cccc} 1 &1 & 1 &1 \\a &b & c & d\\ a^2 &b^2 & c^2 & d^2\\a^4 &b^4 & c^4 & d^4 \end{array}\right|$$
长得太像范德蒙行列式了,做如下镶边:
$$\left |\begin{array}{cccc} 1 &1 & 1 &1 &1 \\a &b & c & d &x\\ a^2 &b^2 & c^2 & d^2 &x^2\\ a^3 &b^3 & c^3 & d^3 &x^3\\a^4 &b^4 & c^4 & d^4 &x\end{array}\right|$$= (x-a)(x-b)(x-c)(x-d)(d-c)(d-b)(d-a)(c-b)(c-a)(b-1)
此时,原行列式就是$$x^3$$所在行的余子式,我们仅看 $$x^3$$项的系数(负的原行列式的值)就得出原行列式的值:
(a+b+c+d)(d-c)(d-b)(d-a)(c-b)(c-a)(b-1)
1、拉格朗日插值法 / 线形递归方程通解
https://blog.csdn.net/ccnt_2012/article/details/82254575
2、纠删码
http://139.196.53.116/ml/index.php/archives/203/
3、计算f(x) = sin(a1t)+sin(a2t)+sin(a3t)+...最小正周期
https://www.zhihu.com/question/20223034
4、基本的斜对称多项式
https://www.zhihu.com/question/20223034
https://www.zhihu.com/question/309243881?sort=created
https://www.cnblogs.com/gzy-cjoier/p/9741950.html
https://ccjou.wordpress.com/2012/06/13/vandermonde-矩陣的逆矩陣公式/