Given: A coin is tossed if head occurs,a die is thrown and if shows even number (2,4,6) the die is thrown again

If represented diagramatically

$\therefore$ The sample space S will be

$S=\left\{\begin{array}{1 1}T,H1,H3,H5,H21,H22,H23,H24,H25,\\H26,HH1,HH2,HH3,HH4,HH5,HH6,\\H61,H62,H63,H64,H65,H66\end{array}\right\}$