especies combinatóries: parts dos

[ m·( {a_{i_{k}},a_{j_{k}}} ) ]


∑ ( ( m·[ k // 2 ] )·x^{k} )


[ m·( {a_{i_{k}},a_{j_{k}}} ) ] + [ n·( {a_{i_{k}},a_{j_{k}}} ) ] = ...
... [ (m+n)·( {a_{i_{k}},a_{j_{k}}} ) ]


∑ ( ( (m+n)·[ k // 2 ] )·x^{k} )


[ m·( {a_{i_{k}},a_{j_{k}}} ) ] [x] [ n·( {a_{i_{k}},a_{j_{k}}} ) ] = ...
... [ (m·n)·( {a_{i_{k}},a_{j_{k}}} [x] {a_{i_{k}},a_{j_{k}}} ) ]


∑ ( ( (m·n)·[ k // 2 ]^{2} )·x^{k} )