Whitespace inside :nth-child()

The following will have a aqua background if the selector given parses:

:nth-child(3n+1)

:nth-child( 3 n + 1 )

:nth-child( 3n+1 )

:nth-child(3n +1)

:nth-child(3n+ 1)

:nth-child(3n-1)

:nth-child(3n -1)

:nth-child(3n- 1)

:nth-child( 3n)

:nth-child(3 n)

:nth-child(3n )

:nth-child(- 3n)

:nth-child( -3n)

:nth-child(-3 n)

:nth-child(3)

:nth-child( 3)

:nth-child(3 )

:nth-child(-3)

:nth-child( -3)

:nth-child(- 3)

:nth-child(-3 )

:nth-child(odd)

:nth-child( odd)

:nth-child(odd )