Questions tagged [palindrome]

A palindrome is a number or any other sequence of characters which remains the same when it is reversed (read backwards). Questions involving palindromes, or mathematics related to them such as the Lychrel process or Scheherazade numbers.

A palindrome is a number or any other sequence of characters which remains the same when it is reversed (read backwards).

Usually we talk about palindromic numbers (numeral palindromes) as positive integers that remain the same when their digits are reversed. As such, palindromes are dependent on the they are observed in.

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How to prove $B-1$ and $B+1$ are always palindromes in base $B$?

While driving to work I thought about a rule, problem is I don't know how to prove it. The rule is: For any base $B$ there will always be two palindrome numbers $A$ and $C$, whose values are: $A=(B+1), C=(B-1)$ $A$ is always $11$ - a palindrome, and…
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palindrome number

How to find the $n$-th term of the series. 1 11 101 1001 10001 100001 1000001
srox
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Find all the numbers such that "Sum of cube of digits=Number itself"

I want to find all the numbers such that "Sum of cube of digits=Number itself". For example, I am seeking for numbers like $153$ as $1^3+5^3+3^3=153$ I know by hit and trial that there are 6 such numbers ( $0,1,153,370,371,407$), But I need it in a…
Atul Mishra
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palindrome 4th grade

This is a 4th grade question. A palindrome is an integer number that does not change when read backwards. E.g. 123321 is a 6 digit palindrome. How many 9-digit palindromes are there that use only the digits 9 and 0? I have created a table and typing…
user39531
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nth term of the series containing one 9 then two 9 and so on

nth term of the series 9, 99, 999, 9999. Is there any formula for it? 9 99 999 9999 . . . .
srox
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