Homotopy group with coefficients
In topology, a branch of mathematics, for i ≥ 2 {\displaystyle i\geq 2} , the i-th homotopy group with coefficients in an abelian group G of a based space X is the pointed set of homotopy classes of based maps from the Moore space of type ( G , i ) {\displaystyle (G,i)} to X, and is denoted by π i ( X ; G ) {\displaystyle \pi _{i}(X;G)} . For i ≥ 3 {\displaystyle i\geq 3} , π i ( X ; G ) {\displaystyle \pi _{i}(X;G)} is a group.
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