Laurent polynomial劳伦特多项式的系数pkp_kpkpk∈Fp_k\in FpkF,F为域,kkk为整数(可为正数和负数),具体可表示为:
p=∑kpkXk=p−kX−k+p−(k−1)X−(k−1)+...+p0+p1X+...+pkXkp=\sum_{k} p_kX^k=p_{-k}X^{-k}+p_{-(k-1)}X^{-(k-1)}+...+p_0+p_1X+...+p_kX^kp=kpkXk=pkXk+p(k1)X(k1)+...+p0+p1X+...+pkXk

Laurent polynomial劳伦特多项式具有如下加法和乘法特性:

  • (∑iaiXi)+(∑ibiXi)=∑i(ai+bi)Xi(\sum_{i}a_iX^i)+(\sum_{i}b_iX^i)=\sum_{i}(a_i+b_i)X^i(iaiXi)+(ibiXi)=i(ai+bi)Xi
  • (∑iaiXi)⋅(∑jbjXj)=∑k(∑i<=k,j;j=k−iaibj)Xk(\sum_{i}a_iX^i)\cdot (\sum_{j}b_jX^j)=\sum_{k}(\sum_{i<=k,j;j=k-i}a_ib_j)X^k(iaiXi)(jbjXj)=k(i<=k,j;j=kiaibj)Xk

参考资料:
[1] http://mathworld.wolfram.com/LaurentPolynomial.html
[2] https://en.wikipedia.org/wiki/Laurent_polynomial

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