/* XKron */
/** Elementary Kronicker, Step and even odd simplifications */
Kron[$i_=Numbp[$i]] :: $i=0
step[$i_=Numbp[$i]] :: $i>=0;

even[0] : 1; even[$j_=Numbp[$j]] :: Evenp[$j]
odd[0] : 0;  odd[$j_=Numbp[$j]] :: Oddp[$j]

