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Square dates

Writing 30 May 2009 in the order day’s number.month.year, with just one digit for the month but the year in full, gives 30.5.2009. This is a perfect square date because 3052009 = 1747². If two digits are allocated for the month, then 3 May 2009 (3.05.2009) was a perfect square date.

If you maintain the order day’s number.month.year and write the year as a four-digit number, as in these examples, what is the next date that will be a perfect square (a) if you allocate one digit for the month, and (b) if you allocate two digits for the month? Give your answers in the form of (a) 30.5.2009, (b) 3.05.2009.

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 1 July. The Editor’s decision is final. Please send entries to Enigma 1547, New Å®ÉúСÊÓƵ, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1541 Box clever: The digits in the boxes are 2, 3, 4, 6, 2, 1, 3, 3, 3 and 6

The winner Tessa Fullwood of Frimley, Surrey, UK