Sphere chain complex
= Sphere chain complex
{title2=$S^n(R)$}
= Sphere complex
{synonym}
The <chain complex> with $R$ in a single degree $n$ and zero differential. A map from it into a complex chooses a cycle in degree $n$.
= Sphere chain complex
{title2=$S^n(R)$}
= Sphere complex
{synonym}
The <chain complex> with $R$ in a single degree $n$ and zero differential. A map from it into a complex chooses a cycle in degree $n$.