Proper divisors: Difference between revisions

</pre>

=={{header|tbas}}==

<lang vb>

dim _proper_divisors(100)

sub proper_divisors(n)

dim i

dim _proper_divisors_count = 0

if n <> 1 then

for i = 1 to (n \ 2)

if n %% i = 0 then

_proper_divisors_count = _proper_divisors_count + 1

_proper_divisors(_proper_divisors_count) = i

end if

next

end if

return _proper_divisors_count

end sub

sub show_proper_divisors(n, tabbed)

dim cnt = proper_divisors(n)

print str$(n) + ":"; tab(4);"(" + str$(cnt) + " items) ";

dim j

for j = 1 to cnt

if tabbed then

print str$(_proper_divisors(j)),

else

print str$(_proper_divisors(j));

end if

if (j < cnt) then print ",";

next

print

end sub

dim i

for i = 1 to 10

show_proper_divisors(i, false)

next

dim c

dim maxindex = 0

dim maxlength = 0

for t = 1 to 20000

c = proper_divisors(t)

if c > maxlength then

maxindex = t

maxlength = c

end if

next

print "A maximum at ";

show_proper_divisors(maxindex, false)

</lang>

<pre>

>tbas proper_divisors.bas

1: (0 items)

2: (1 items) 1

3: (1 items) 1

4: (2 items) 1,2

5: (1 items) 1

6: (3 items) 1,2,3

7: (1 items) 1

8: (3 items) 1,2,4

9: (2 items) 1,3

10: (3 items) 1,2,5

A maximum at 15120:(79 items) 1,2,3,4,5,6,7,8,9,10,12,14,15,16,18,20,21,24,27,28,30,

35,36,40,42,45,48,54,56,60,63,70,72,80,84,90,105,108,112,120,126,135,

140,144,168,180,189,210,216,240,252,270,280,315,336,360,378,420,432,

504,540,560,630,720,756,840,945,1008,1080,1260,1512,1680,1890,2160,

2520,3024,3780,5040,7560