答案1
欢迎光临!与tikz-cd
。
\documentclass{article}
\usepackage{tikz-cd}
\begin{document}
\[
\begin{tikzcd}[every arrow/.append style={-stealth}]
\cdots \arrow[r]& H^k(B) \arrow[r]& H^k(C)\arrow[r] & H^k(D)
\arrow[dll,out=-10,in=170,overlay,looseness=1.2,"\delta" {marking,fill=white}]\\
& H^{k+1}(B)\arrow[r] & H^{k+1}(C)\arrow[r] & H^{k+1}(D)
\arrow[dll,out=-10,in=170,overlay,looseness=1.2,"\delta" {marking,fill=white}]\\
& H^{k+2}(B) \arrow[r]& H^{k+2}(C)\arrow[r] &\cdots \\
\end{tikzcd}
\]
\end{document}
答案2
使用matrix
Ti 库钾Z:
\documentclass[tikz,border=3.14]{standalone}
\usetikzlibrary{matrix}
\begin{document}
\begin{tikzpicture}
\matrix (H) [matrix of math nodes, column sep=4ex, row sep=1ex]
{%
\vphantom{H}\ldots & H^k(B) & H^k(C) & H^k(D) \\
& H^{k+1}(B) & H^{k+1}(C) & H^{k+1}(D) \\
& H^{k+2}(B) & \vphantom{H}\ldots \\
};
\draw[->] (H-1-1) -- (H-1-2);
\foreach\r in {1,2}
\foreach\n in {2,3}
\draw[->] (H-\r-\n) -- (H-\r-\the\numexpr\n+1\relax);
\draw[->] (H-3-2) -- (H-3-3);
\foreach\r in {1,2}
\draw[->] (H-\r-4.east) to[out=-10,in=170]node[fill=white,inner
sep=1pt]{$\delta$} (H-\the\numexpr\r+1\relax-2.west)
;
\end{tikzpicture}
\end{document}