[ale] regex assistance

[brock at quantifier.org]

> Why does this request seem like a school assignment?

Beats me.  In fact, what I'm doing is this: I'm a freelance editor for a 
textbook publisher.  I get long lits of texts from other publishers, but in 
an excel file, with one column of title, one of author, and one of isbn. 
I have to choose which  ones to send out to other editors, which ones to 
look at, and which to ignore.  This is difficult with only the title. 
Amazon gives you the option to concatonate search terms by isbn, like 
this:

747474747 | 656565656

will return those two books.  Looking at the cover, and then having the 
ability to quickly learn more about them makes my job much easier.  So 
what you're helping me with is to convert this:

6565656565
7474747474

to this:

65656565 | 767676767667

to make my job easier.  I guess someone might assign this as homework.  I 
don't know -- it's been a long while since anyone has assigned me 
homework.

Thanks again for all of your help.