Proper divisors: Difference between revisions

===Functional===

----

===Idiomatic===

<lang applescript>on properDivisors(n)

set output to {}

if (n > 1) then

set sqrt to n ^ 0.5

if (sqrt mod 1 is 0) then

set end of output to sqrt as integer

set sqrt to sqrt - 1

end if

repeat with i from (sqrt div 1) to 2 by -1

if (n mod i is 0) then

set beginning of output to i

set end of output to n div i

end if

end repeat

set beginning of output to 1

end if

return output

end properDivisors

-- Task code.

local output, astid, i, maxPDs, maxPDNums, pdCount

set output to {}

set astid to AppleScript's text item delimiters

set AppleScript's text item delimiters to ", "

repeat with i from 1 to 10

set end of output to (i as text) & "'s proper divisors: {" & properDivisors(i) & "}"

end repeat

set maxPDs to 0

set maxPDNums to {}

repeat with i from 1 to 20000

set pdCount to (count properDivisors(i))

if (pdCount > maxPDs) then

set maxPDs to pdCount

set maxPDNums to {i}

else if (pdCount = maxPDs) then

set end of maxPDNums to i

end if

end repeat

set end of output to linefeed & "Largest number of proper divisors in any number from 1 to 20,000: " & maxPDs

set end of output to "Numbers with this many: " & maxPDNums

set AppleScript's text item delimiters to linefeed

set output to output as text

set AppleScript's text item delimiters to astid

return output</lang>

{{output}}

<lang applescript>"1's proper divisors: {}

2's proper divisors: {1}

3's proper divisors: {1}

4's proper divisors: {1, 2}

5's proper divisors: {1}

6's proper divisors: {1, 2, 3}

7's proper divisors: {1}

8's proper divisors: {1, 2, 4}

9's proper divisors: {1, 3}

10's proper divisors: {1, 2, 5}

Largest number of proper divisors for any number from 1 to 20,000: 79

Numbers with this many: 15120, 18480"</lang>