75
votes
Print some JSON
Python 2, 14 bytes
print{`str`:1}
Outputs:
{"<type 'str'>": 1}
The backticks get the string representation in Python ...
51
votes
Print all integers
Haskell, 19 bytes
do n<-[1..];[1-n,n]
Produces the infinite list [0,1,-1,2,-2,3,-3,4,-4,5,-5,6,-6,7,-7...
Haskell allows ...
41
votes
Print some JSON
jq, 6 characters
(3 characters code + 3 characters command-line option.)
env
CW because I am sure this is not the kind of answer you intended to allow.
Sample ...
34
votes
Write a program whose nontermination is independent of Peano arithmetic
Haskell, 838 bytes
“If you want something done, …”
...
33
votes
Print some JSON
Jelly, 11 bytes
“Ɠɼ'ẸẠḌȷżÑ»
Try it online!
Output
{"Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch":0}
32
votes
31
votes
Print all integers
Brainfuck, 6 bytes
This makes use of the cell wrapping and prints all possible values. In Brainfuck, the native integer representation is by byte value.
.+[.+]
Try ...
31
votes
Print all integers
Cubix, 14 12 bytes
.(.\OSo;?.>~
Test it online! You can now adjust the speed if you want it to run faster or slower.
How it works
The first thing the ...
31
votes
What an Odd Function
Jelly, 7 bytes
Æf^<¥4P
Swaps 2s and 3s in the input's prime factorization. The probability of odds is 2/3.
Try it online!
How it works
...
30
votes
Egyptian fraction representations of 1
Python 2, 42 bytes
f=lambda n,x=1:1/n*[x]or[x+1]+f(n-1,x*-~x)
Try it online!
The key thing to observe is that ...
26
votes
Infinitely many ℕ
Scratch 3.0, 13 20 blocks/121 70 bytes
As SB Syntax:
define(n)(i
say(i
((n)+<(i)=(n)>)((1)+((i)*<(i)<(n
This says each term in the sequence. A delay ...
26
votes
Give me odd, even, square, cube, prime and composite 3-digit numbers
Python 2, 25 22 bytes
lambda s:hash(s)%591^1
Try it online!
Takes input in upper case and returns the following numbers:
...
25
votes
Be big more often
Python, 41 bytes
lambda l:choices(l,l)
from random import*
Attempt This Online! or run it 100000 times
Uses the list itself as the weights.
22
votes
Accepted
Print all integers
Sesos, 113 3 bytes
0000000: c4ceb9 ...
Try it online! Check Debug to see the generated SBIN code.
Sesos assembly
The ...
22
votes
Print some JSON
Notepad, 7 keystrokes
If you have a Windows computer with the Notepad program, type this:
{"F5":0}
On my Windows 7 computer, at least, this gives you something like:
...
21
votes
Print all integers
Python 2, 27 bytes
n=0
while 1:print~n,n,;n+=1
Prints -1 0 -2 1 -3 2 -4 3 ...
21
votes
Print all integers
MATL, 8 bytes
0`@_@XDT
This uses MATL's default data type, which is double, so it works up to ...
21
votes
Accepted
Demonstrate some advanced abstract algebra
Proof of impossibility
The only anti-distributive operator when \$S=\mathbb Z\$ is such that \$\forall a, \forall b, a*b=0\$.
Indeed, suppose that \$*\$ is anti-distributive. Then \$*\$ has the ...
20
votes
20
votes
f(g(x)) decreases while g(f(x)) increases
Python, 68 characters
f=lambda x:(1-x%2*2)*(2*x*x+(x<0))
g=lambda x:(1-x%2*2)*(2*x*x+(x>0))
f maps negative numbers to odd numbers and positive numbers to ...
20
votes
Bijective function ℤ → ℤⁿ
Alice, 14 12 bytes
/O
\i@/t&Yd&
Try it online!
Inverse function (not golfed):
/o Q
\i@/~~\ /dt&Z
Try it ...
19
votes
Infinitely many ℕ
Husk, 2 bytes
ḣN
Try it online!
First Husk answer! Also uses the sequence in the question
How it works
...
18
votes
Injection from two strings to one string
brainfuck, 30 29 27 23 bytes
,[-[+.>]-[>+<---]>.-.,]
Try it online!
Inputs are separated by a 0x01 byte.
This ...
18
votes
Enumerate all pure sets
Python, 43 bytes
f=lambda x:[f(i)for i in range(x)if x>>i&1]
Attempt This Online!
Outputs the \$ n \$th set, starting at \$ 0 \$.
One way of creating a sequence of all pure sets is to encode ...
18
votes
Create a nibble shorthand
MATL, 12 7 bytes
t~Pv1YG
Input is a 4-digit binary vector.
Example outputs (or try it at MATL Online!):
Input [0 1 0 0]:
...
17
votes
Print some JSON
Java (JDK 10), 20 bytes
v->"{\"\":"+1/.3+"}"
Try it online!
Output
{"":3.3333333333333335}
17
votes
Golf a bijection within the natural numbers which map the primes to a proper subset of the primes
Mathematica, 54 48 bytes
±(t=x_?PrimeQ)=NextPrime@x
±n_:=Abs[n-1]/.t:>x-1
Defines the following bijection:
...
17
votes
Walk Across a Keyboard
Python 2, 83 bytes
lambda s:re.findall('.*?'.join(s),'qwertyuioplkmnjhbvgfcxdsza'*len(s))[0]
import re
Try it online!
Walks the entire keyboard until the word ...
Only top scored, non community-wiki answers of a minimum length are eligible
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