David Wilson davidwwilson at attbi.com
Sun May 25 15:37:01 CEST 2003

The concept of "palindromes with possible trailing zeroes" crops up repeatedly.
What if we give them a name, say quasipalindromes?  Then we could use the
term to dispense with both "ignoring leading/trailing zeroes" and "0 if undefined"
babble, both of which I find distasteful.

The same problem with leading/trailing zeroes pops up in the closely allied
concept of digit reversals.  There are four possible variants, according to
whether we permit leading zeroes on the number and/or its reverse.  It
might be good to look at standards for that too.

I also find this issue in digital permutations.  In my terminology, I tend to use
"permutation" if leading zeroes are allowed in the permuted number, and
"anagram" if not.  My logic is that an anagram of a word must be a proper
word, not a meaningless jumble of characters.  So that anagram of a numeral
must be similarly be a proper numeral, which typically does not include a
leading zeroes.  Tenuous logic, but useful.

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