checking the factors are of 4 t + 3 form or not
if ( ( $ n % $ i == 0 ) && ( ( $ i - 3 ) % 4 ) == 0 ) { $ q = ( int ) $ n / $ i ; return ( $ q != $ i && $ prime [ $ q ] && ( $ q - 3 ) % 4 == 0 ) ; } } } return false ; }