printf( "Starting the loop test...\n" );

f = function( k ) {
    if ( k == 1 ) { return 1; }
    for ( i in 1:k-1 ) {
        k += f( i );
    }
    return k;
};

if ( f(3) == 7 & f(4) == 15 ) {
    printf( "...passed.\n" );
else
    printf( "...failed.\a\n" );
    exception();
}