Search Results
Search type | Search syntax |
---|---|
Tags | [tag] |
Exact | "words here" |
Author |
user:1234 user:me (yours) |
Score |
score:3 (3+) score:0 (none) |
Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
Views | views:250 |
Code | code:"if (foo != bar)" |
Sections |
title:apples body:"apples oranges" |
URL | url:"*.example.com" |
Saves | in:saves |
Status |
closed:yes duplicate:no migrated:no wiki:no |
Types |
is:question is:answer |
Exclude |
-[tag] -apples |
For more details on advanced search visit our help page |
The challenge involves mathematics in some central way. Also consider using more specific tags, listed in the tag wiki info.
1
vote
Lonely Multiplication
PowerShell, 97 bytes
param($n)$a,$b,$c=$n|group;(($n-join'*'|iex),(($a,$b|?{$_.count-eq1}).name,1)[$a.count-eq3])[!$c]
Try it online!
Not terribly impressive, but given that PowerShell doesn't h …
2
votes
Shift right by half a bit
PowerShell, 67 bytes
param([uint64]$n)($n/[math]::Sqrt(2)).ToString("G17")-replace'\..*'
Try it online! … However, the [math]::Sqrt() function only works on Double, so there we're stuck. So far, so standard. …
3
votes
Multiplicative persistence
PowerShell, 64 59 bytes
for($a="$args";9-lt$a){$a;$a="$(($a|% t*y)-join'*'|iex)"}$a
Try it online!
Iterative method. Takes input and stores it into $a, then enters a for loop so long as the leng …
0
votes
Smallest Diversifying Exponent
PowerShell, 107 bytes
param([bigint]$a)for([bigint]$b=1;-join("$([bigint]::pow($a,$b))"|% t*y|sort -u)-ne-join(0..9);$b=$b+1){}$b
Try it online!
Pretty straightforward, just a shame we need to u …
2
votes
Sum \$\text{Square}^2\$
PowerShell, 68 56 bytes
param($n)1..$n|%{$a+=$_*$_*!($n%$_)};1..$a|?{$_*$_-eq$a}
Try it online!
Seems long ...
-12 bytes thanks to mazzy
Does exactly what it says on the tin. Takes the range fr …
3
votes
Calculate power series result
$n|%{$o+=[math]::pow($x,$_)};$o
Try it online!
Not bad for needing a .NET call for pow.
-7 bytes thanks to mazzy. …
2
votes
count ones in range
PowerShell, 72 bytes
param($x,$y)$x..$y|%{$o+=([convert]::ToString($_,2)-replace0).length};$o
Try it online!
Long because of the conversion to binary [convert]::ToString($_,2) and getting rid of …
5
votes
Detect heat waves
PowerShell, 121 bytes
param($a)$b="";($a|%{if($_-ge25){$b+="$_ "}else{$b;$b=""}})+$b|?{(-split$_).count-ge5-and(-split$_|?{$_-ge30}).count-ge3}
Try it online! or Verify all test cases
PowerShell …
17
votes
14
answers
2k
views
Conway's Prime Game
Specifically, Conway's PRIMEGAME.
This is an algorithm devised by John H. Conway to generate primes using a sequence of 14 rational numbers:
A B C D E F G H I J K L M N
17 …
23
votes
32
answers
2k
views
Rotational Average
Given an input integer n >= 10, output the average of all deduplicated rotations of the integer.
For example, for input 123, the rotations are 123 (no rotation), 231 (one rotation) and 312 (two rotat …
5
votes
Converting ISBN-13 to ISBN-10
PowerShell, 96 84 bytes
$y=-(([char[]]($x="$args"-replace'^978|.$')|%{--$a*[int]"$_"})-join'+'|iex)%11;$x+$y
Try it online!
Takes input "$args", does a regex -replace to get only the pertinent p …
1
vote
Are the numbers amicable?
PowerShell, 87 96 bytes
param($a,$b)filter f($n){(1..($n-1)|?{!($n%$_)})-join'+'|iex}(f $a)-eq$b-and(f $b)-eq$a-and$a-$b
Try it online!
Takes input $a,$b. Defines a filter (here equivalent to a …
1
vote
Prime numbers between n and 2n
PowerShell, 57 bytes
param($n)(2*$n-1)..++$n|?{'1'*$_-match'^(?!(..+)\1+$)..'}
Try it online!
Takes input $n, constructs a range from 2*$n-1 to ++$n (i.e., excluding the endpoints), and feeds th …
0
votes
What is the missing number (divisibility by 9)
PowerShell, 40 bytes
param($a)0..9|?{!(($a-replace'x',$_)%9)}
Try it online! or Verify all test cases
Takes input like '123x' into $a. Constructs a range 0 to 9 and uses Where-Object (here abbre …
2
votes
Iterated phi sequence
PowerShell, 110 bytes
$a=,0*101;2..100|%{$i=$_;for($z=$j=0;++$j-lt$i;$z+=$k-eq1){for($k=$j;$j%$k-or$i%$k;$k--){}};($a[$i]=$a[$z]+1)}
Try it online!
Mathematical approach.
Actually, looking thro …