palindrome number

Question

How to find the $n$-th term of the series.

1

11

101

1001

10001

100001

1000001

$10001$ is a palindrome as well – Peter Mar 08 '19 at 16:45 — Peter, Mar 08 '19 at 16:45

score 4 · Accepted Answer · edited Mar 08 '19 at 17:09

4

The smallest $n$-digit palindrome is $$10^{n-1}+1: n>1$$

edited Mar 08 '19 at 17:09

postmortes

answered Mar 08 '19 at 16:44

Peter

3

except when n=1 of course! – DCarter Mar 08 '19 at 16:48
@DCarter Yes, then it is $1$ (or $0$) and not $2$ – Peter Mar 08 '19 at 16:50
I am not able to upvote.Pease help. – srox Mar 08 '19 at 16:59
Also not true when n=0 for those who like the initial term to be $P_0$. I've edited the answer to make it technically correct. – Martin Hansen Mar 08 '19 at 17:11
@MartinHansen A $0$-digit number makes no sense to my opinion. But the restriction to $n>1$ is a useful edit. – Peter Mar 08 '19 at 17:42
@Peter, Yes I agree ! – Martin Hansen Mar 08 '19 at 17:55

1 Answers1