Repeated Concatenation
Number Theory
Level
3
Concatenating four copies of 23 produces \(23 || 23 || 23 || 23 = 23232323.\)
Now, suppose you concatenate \(x\) copies of any positive integer \(n.\)
What is the minimum value of \(x\) such that the result of this concatenation is guaranteed to be a multiple of 11?
by
Stephen Mellor