https://wiki.cvbbacm.com/ 2026-04-30T02:29:43+0800 https://wiki.cvbbacm.com/ https://wiki.cvbbacm.com/lib/exe/fetch.php?media=favicon.ico text/html 2020-06-06T19:51:51+0800 Anonymous (anonymous@undisclosed.example.com) https://wiki.cvbbacm.com/doku.php?id=2020-2021:teams:farmer_john:2sozx:problem:fib%E6%95%B0%E5%88%97&rev=1591444311&do=diff fib数列 题意：$f(x+1)=f(x)+f(x-1)+(-1)^n+x\%5+\lfloor{\log_{2}{x}}\rfloor,f(1)=f(2)=1$ ，求第 $n$ 项。 $n\le10^{18}$ 题解：构造两个矩阵$$A=\left(\begin{array} {} 1 & 1 & 1 & 1 & 0 & 0 & 0 & 0 & 0 \\ 1 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & -1 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 2 & 3 & 4 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 0 & 1 & 0 {} \end{array}\right) ,…