HOW TO RETURN proper.divisor.sum.table n:
    PUT {} IN propdivs
    FOR i IN {1..n}: PUT 1 IN propdivs[i]
    FOR i IN {2..floor (n/2)}:
        PUT i+i IN j
        WHILE j<=n:
            PUT propdivs[j] + i IN propdivs[j]
            PUT i + j IN j
    RETURN propdivs

PUT 20000 IN maximum
PUT proper.divisor.sum.table maximum IN propdivs

FOR cand IN {1..maximum}:
    PUT propdivs[cand] IN other
    IF cand<other<maximum AND propdivs[other]=cand:
        WRITE cand, other/