11 | abba, where a and b are the digits in a 4 digit number.
Nov 21, 2013 · Truly lost here, I know abba could look anything like 1221 or even 9999. However how do I prove 11 divides all of the possiblities?
How many $4$-digit palindromes are divisible by $3$?
Feb 28, 2018 · Hint: in digits the number is $abba$ with $2 (a+b)$ divisible by $3$.
prove $\\Gamma(a)\\Gamma(b) = \\Gamma(a+b)B(a,b)$ using …
Jun 23, 2022 · Are you required to make it wiht polar transformation? Because with the change $x=uv$ $y=u (1-v)$ it's easier
elementary number theory - Common factors for all palindromes ...
For example a palindrome of length $4$ is always divisible by $11$ because palindromes of length $4$ are in the form of: $$\\overline{abba}$$ so it is equal to $$1001a+110b$$ and …
How to calculate total combinations for AABB and ABBB sets?
Apr 19, 2022 · Although both belong to a much broad combination of N=2 and n=4 (AAAA, ABBA, BBBB...), where order matters and repetition is allowed, both can be rearranged in different …
matrices - When will $AB=BA$? - Mathematics Stack Exchange
Aug 29, 2013 · You'll need to complete a few actions and gain 15 reputation points before being able to upvote. Upvoting indicates when questions and answers are useful. What's reputation …
sequences and series - The Perfect Sharing Algorithm (ABBABAAB ...
Oct 4, 2016 · The algorithm is normally created by taking AB, then inverting each 2-state 'digit' and sticking it on the end (ABBA). You then take this entire sequence and repeat the process …
$A^2=AB+BA$. Prove that $\\det(AB-BA)=0$ - Mathematics Stack …
I get the trick. Use the fact that matrices "commute under determinants". +1
Matrices - Conditions for $AB+BA=0$ - Mathematics Stack Exchange
You'll need to complete a few actions and gain 15 reputation points before being able to upvote. Upvoting indicates when questions and answers are useful. What's reputation and how do I …
Find a generating function for the number of strings
May 13, 2016 · I do realize that the method that you show in your post is more powerful than what I presented. Otherwise with non-trivial words you have to construct a DFA from the prefixes of …