scope /*  show members of the van der Corput sequence in various bases
       *       translated from the C sample
       */

    # returns the numerator and denominator of the nth member of the van der Corput sequence
    #          in the specified base
    local proc vc( nth :: number, base :: number )
        local p, q, n := 0, 1, nth;

        while n <> 0 do
            p *:= base;
            p +:= n mod base;
            q *:= base;
            n \:= base
        od;

        # return the numerator and denominator reduced by their gcd
        local num, denom := p, q;
        q := numtheory.gcd( p, q );
        return num \ q, denom \ q
    end;

    # task
    for b from 2 to 5 do
        printf( "base %d:", b );
        for i from 0 to 9 do
            local n, d := vc( i, b );
            if n <> 0 then printf( "  %d/%d", n, d ) else printf( "  0" ) fi
        od;
        io.write( "\n" )
    od
epocs