calculator sequence inspired by my calendar

[Tanya Khovanova]

I am looking for the numbers that can be represented as the difference of a number and its ipside down version on a calculator. I think I can prove that 15 is not there, but I do not have a systematic way to build this sequence.


---------- Original Message ----------------------------------
From: "jos koot" <jos.koot at telefonica.net>
Date:  Thu, 21 Dec 2006 00:27:15 +0100

>Here are some solutions:
>Greetings, Jos Koot
>mabel 12, zane 21
>mabel 15, zane 51
>mabel 16, zane 91
>mabel 18, zane 81