6174 - Numberphile

jsndacruz Says:

May 20, 2012 - I was looking for a formal proof, which can be found in "The determination of all decadic Kaprekar constants," Fibonacci Quart (1981). Apparently 6178 and 495 are the only ones, but in modulus notation there are others, as shown by Walden, "Searching for Kaprekar's Constants: algorithms and results."

ard5608 Says:

May 20, 2012 - Follow the same steps as in the video, but with one digit less? Example: 168 861-168=693 963-369=594 954-459=495

jsndacruz Says:

May 19, 2012 - How do you prove that you always get to a 3-digit with 4,9, and 5?

zippyman28 Says:

May 19, 2012 - For 5 digits it is 61974 74321-12347 = 61974 97641-14679 = 82962 98622-22689 = 75933 97533-33579 = 63954 96543-34569 = 61974

SimonZBox Says:

May 17, 2012 - For two digits it works, it's just that you include the 0 in, for example, 98 - 89 = 09, not just 9 so after it's 90 - 09 = 81, etc. and it loops to 9 all the time.

AngelFlonisH Says:

May 16, 2012 - Cool!!!! yay! another new game to amaze my boyfriend! i hope he won't find this video EVER! yay!

rimas541997 Says:

May 15, 2012 - 9998 9990 9981 8820 8532 8999 0999 1899 0288 2358 0999 8991 8082 8532 6174 

robinvik1 Says:

May 15, 2012 - What if you do this in binary?

scyther384 Says:

May 14, 2012 - 3267 

soggywedge Says:

May 14, 2012 - Yes it does

mhssoccer1309 Says:

May 13, 2012 - BTW this doesnt work with 9998.

mhssoccer1309 Says:

May 13, 2012 - now the challenge is to see who can come up with a number that takes the most turns to get to 6174....

XEXTRADIESELX Says:

May 13, 2012 - if you the same thing with a 3 digit number you should end up with the number 495 over and over again. If you do it with a 2 digit number it should always en up in 0 but the last number before the 0 is gonna be 9. THUMBS UP IF YOU TESTED IT AND IT WORKS!

PoketoMtg Says:

May 12, 2012 - 2*3^2*7^3. I wonder if that leads to more interesting things about it.

ipoopmypants271 Says:

May 12, 2012 - Omg yes!!!

MrGquad Says:

May 11, 2012 - 0001?

Jdog314159 Says:

May 10, 2012 - Is it a coincidence that this number is fairly close to the golden ratio * 1000?

ToyOverload Says:

May 8, 2012 - 5085?

zebezd Says:

May 2, 2012 - 1000 - 0001 = 0999 9990 - 0999 = 8991 9981 - 1899 = 8082 8820 - 0288 = 8532 8532 - 2358 = 6174 Works like a charm, just took 5 rounds. In fact, after the first round it's exactly the same as one of the current top voted comments, now that I look at it.

waterproofcat1 Says:

May 2, 2012 - is this really the shit these mathematicians work on, pseudo finite exceptionality 

ryansprintsta Says:

Apr 29, 2012 - and eith 3 digits its either 99 or 495

ryansprintsta Says:

Apr 29, 2012 - this happens with 9 on a 2 digit scale

igotdembombs Says:

Apr 27, 2012 - 1000-0001=0999 9990-0999=8991 9981-1899=8082 8820-0288=8532 8532-2358=6174 You have to keep them as 4 digit numbers :) fux4k3 in reply to saifbab1 2 weeks ago 2 If you scrolled down a little bit you would have seen it in the comments.

Ibakecookiess Says:

Apr 26, 2012 - 1000-0001=0999 9990-0999 = 8991 9981-1899 = 8082 8820-0288 = 8532 8532-2358 = 6174