This is a followup to my original April 13th message. After running for about a month, the program finally finished running yesterday. I'm pleased with what it found. It tried all 1,679,616 (6^8) possible ways of sticking zero or more plus signs, minus signs, times signs, divide signs, and decimal points into PONDER=THIS, to see which ones have a unique solution. (Infix only, no prefix plus or minus. No parentheses. Each letter represents a unique digit. Note that there are ten letters with no duplicate letters.) 1,019,744 of the 1,679,616 arrangements of operations had at least one solution. 1065 of them had exactly one solution. And just 1 of those 1065 had a set of operations not shared by any others. I could stop here and say find that one (a meta-meta- problem). But I won't be that cruel. The unique solution to the meta-problem is a single division sign and a single minus sign. Insert those into PONDER=THIS so that it has a unique solution. There's exactly one way to do this. Have fun. (There are an additional 5 ways to insert those character into PONDER=THIS that give multiple solutions. For instance POND/E-R=THIS has two solutions: 4608/3-7=1529 and 4608/3-9=1527) At the other extreme, there are 44 ways to insert a plus sign, a multiplication sign, two division signs, and two decimal points to get a problem with a unique solution. I've submitted this to the website, <http://researchweb.watson.ibm.com/ponder/>, where the problem that inspired this appeared, in hopes that they'll use it, with credit to me, in some future month.