Any puzzles here?

@Wen1now MD fails with multiline stuff

Cryptic challenge code clue chains The aim of this is to write obfuscated and/or inefficient code and get other people to try and reverse-engineer it to work out what it does. Similar to the 4Cs in TSL, the answerer to the last 5C gets to write the next challenge.

To get the ball rolling:

5C: tio.run/##RYzLCsMgFET3/…

This one shouldn't be that difficult.. at least I hope it isn't too hard

never mind, my guess didn't work

even better is even

if you're guessing "is an even number", fails for 8

2 or 2*prime

correct

that's what OEIS told me

What's what OEIS told you?

coming up, sorry

when I put the numbers into OEIS there was a sequence with 2 and 2*prime

Oh... I wonder why that'd be in OEIS

There is a lot of unique stuff in that database

should we ban using the OEIS or just avoid creating programs that use things from there?

I'd say we're allowed to use whatever we want

Try it online!

input: space separated non-negative integers

should that be starred, then?

can I be added as a RO?

@boboquack shouldn't this have 5C tag or something?

@boboquack so what exactly are answers supposed to be anyway?

I made a program to implement cyclic tag in an esolang once

@DestructibleLemon what the code does

oh ok

I'm not sure why adding more zeroes to the end causes the number to go down...

i'm not sure why the number jumps into the 900's after there are 3 or more numbers...

I understand what it does

Perhaps we should make these questions more PE-ish

e.g 'Find the last ten digits of the output given input (1 2 3 4 5) or something like that'

what do you mean PE

Project Euler

oh k

Hmm. maybe I don't understand what the code does

but that would be simple since you could just plug it in?

seems tio hits a limit for some reason... let me check something

*correctly for large numbers

@boboquack Are you sure the TIO calculator works correct

Yeah it seems to break for numbers that are modestly large

@Wen1now no, it's doing something weird

okay, so I've hit some sort of recursion limit for TIO, sorry

I was just about to say that :(

@Wen1now wait so are you going to tell the answer

It's actually something pythony

Nah. I know what it does. I don't know how to simplify it though

well if you know what it does you should be able to simplify it?

Note for CCCCC above - some answers will hit the recursion limit and will produce false output, so edit the line with sys.setrecusionlimit()

@thecoder16 That is why it wouldn't be simple

CCCCC: Try it online!

Theoretically, it will call itself >1000 times for sufficiently large input :p

oh that clears things up actually

now works for the test case 1 0 0 0

oh

now it makes sense why it was lower

still doesn't work for 1 0 0 0 0

well...

like if i just say what steps it takes, that doesn't count right?

i'm pretty sure we can all do that just by reading the code...

yes, but i mean "what the code does" isn't very clear

i have a feeling it's something to do with the tower of hanoi

not sure how

but somehow

hmm that could be a decent C5

I believe this is Ross's Massive Integer Sequence function

@Wen1now correct... but only 3 people on Puzzling will understand this

explain it in words

Oh... was that it?

I thought we had to find a general form or something

I think the word explanation is precisely the same as the code

input is actually supposed to be a sequence of 0s and 1s, actually

@Wen1now no, there's a nice interpretation (same way as it was explained)

you can use ordinals if you want

Ordinals only prove that the sequence eventually ends

What woulda been really cool is something like this:

also isn't it always a triangle number too?

tio.run/…

Then it would be precisely as he explained it

wait, my mistake

Anyway it takes an input (e.g [0,1,1,1]) and reverses it to make [1,1,1,0] in that case

Concatenate the digits to get A_0

oh ok

wait what?

that doesn't seem right...

To get A_n, convert A_{n-1} in base n-1 to get a string of digits, K

oh ok

Then interpret that string of digits, K, in base n+1

Then subtract 1

That gives you A_n

how interested would you be in a king of the hill challenge i might be making?

I don't really do much ppcg

yes, but it's not a codegolf

Anyway, the output is the (unique?) i such that A_i=0

+-1 depending on 'off by one' errors

(@boboquack is that sufficiently explained?)

do you win?

@Wen1now yep

it's just that it seems that nobody wants to participate in python, and language agnostic is way too slow, and noone wants to participate in a custom language

grr

This seems like it would be a great cops-and-robbers challenge

not objective?

what?

it seems a bit subjective what is adequately explained

oh, I though you meant lack of an objective winning criterion

that's sort of what i meant though

@Wen your turn again...

Okay

Sorry

Woah what a coincidence

I was messing around with random things

and got this function

what function?

CCCCC: Try it online! Question: What is a(1000,2)?

I can't spell...

(Just writing it in closed form should be enough)

@boboquack It was actually a coincidence...

@Wen1now what was a coincidence?

I've got most of it, but one thing is eluding me

@Wen1now CCCCC guess: 53468279498594739315326409948094090347014100104106127011443144379680517451134312‌​512410599102903223320566974178585902026576838549756046470775563042097745888271633‌​493196372912617251162279261231997970991368943701910168073886924319850120236064290‌​92454394371027042365584541662554485994659569031765628366618625

wait, maybe there's a bug in my program...

Revised answer:

26760927464477026340686915600273545218771085172345701845907665949549517501845279‌​659267629510922004056736676956115889841959048953510165543238871482492809690572826‌​583017623516886089133826143271926840190569927233571271495898315328421979015946005‌​32746462914156320302213906373192350455242940612592115600326656

because that looks a lot nicer

Hmm.... I didn't get either of those

(sorry my wifi at home was broken so I didn't have internet at home)

Just to stop long numbers breaking this room - find the last 10 digits