In a December blog posting, I expressed surprise that the longest DDC Edition 23 numbers I could locate in our database or in WorldCat that are palindromes—the numbers read the same forwards or backwards—were "only" 7 digits long. We declared a contest for the longest valid DDC number that is a palindrome.
Mark Behrens, a classifier in the Dewey Section at the Library of Congress, soon used his Dewey prowess to generate a 12-digit DDC palindrome: 330.977779033, economic conditions of Taylor County, Iowa, in the 20th century (built using 330.9 Economic situation and conditions, plus notation T2—77779 Taylor County, Iowa, plus 033 from 977.7033 [Iowa] 1945–1999 ["Class here 20th century"], following the instructions at 330.93–330.99 [Economic situation and conditions] Specific continents, countries, localities).
Can you find a Dewey palindrome that is longer than 12 digits? You have until the end of January to enter/win the present "contest." (Can there be a contest without a prize? Ah, but isn’t laudable mention of one's name in the Dewey blog prize enough?)