\begin{array}{lll}
1 & {x + y} & {x^{2} + {2yx} + y^{2}} \\
{x + y} & {x^{2} + {2yx} + y^{2}} & {x^{3} + {3yx^{2}} + {3y^{2}x} + y^{3}} \\
{x^{2} + {2yx} + y^{2}} & {x^{3} + {3yx^{2}} + {3y^{2}x} + y^{3}} & {x^{4} + {4yx^{3}} + {6y^{2}x^{2}} + {4y^{3}x} + y^{4}} \\
{x^{3} + {3yx^{2}} + {3y^{2}x} + y^{3}} & {x^{4} + {4yx^{3}} + {6y^{2}x^{2}} + {4y^{3}x} + y^{4}} & {x^{5} + {5yx^{4}} + {10y^{2}x^{3}} + {10y^{3}x^{2}} + {5y^{4}x} + y^{5}} \\
\end{array}
