Games: Perplexity

Two weeks ago, we asked which April dates could not be turned into valid sums using specified arithmetical signs. The ones that don't work are 1.4.97, 3.4.97, 9.4.97, 10.4.97 and 30.4.97. (Of the rest, the 27th and 19th caused most problems:

2x.7x(-4+9)=7 and (-1+9)4=9-7. The best set of answers came from Mike Shepherd of London SE21.

Now, naturally enough, we want to know which dates in May cannot turn into valid sums. Note a slight change in the rules: this time we allow only +, - , , x, = and as many brackets as you want. (Last time we allowed power-raising exponents too.)

A prize of the Chambers 21st Century Dictionary will be awarded to the sender of the best set of answers. Entries by 6 May to: Perplexity, The Independent,

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