F-Orthogonal subgraph

[math]\displaystyle{ {\mathcal F} }[/math]-Orthogonal subgraph --- [math]\displaystyle{ {\mathcal F} }[/math]-ортогональный подграф.

Let be [math]\displaystyle{ {\mathcal F} = \{F_{1}, \ldots, F_{t}\} }[/math] is 1-factorization of [math]\displaystyle{ G }[/math]. A subgraph [math]\displaystyle{ H }[/math] of [math]\displaystyle{ G }[/math] is suborthogonal to [math]\displaystyle{ {\mathcal F} }[/math] if [math]\displaystyle{ |E(H) \cap E(F_{i})| \leq 1 }[/math] for [math]\displaystyle{ 1 \leq i \leq t }[/math], and orthogonal if [math]\displaystyle{ |E(H) \cap E(F_{i})| = 1 }[/math] for [math]\displaystyle{ 1 \leq i \leq t }[/math].