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Doubly square dates

4 April 2001 was the first doubly square date of the century because whether written in the order day.month.year or in the order month.day.year (in each instance with two digits for each element) it comes out as 04.04.01, and 40401 is 201².

Still with two digits for each element, there are some doubly square dates for which the square that comes from the order day.month.year is not the same as the square that comes from the order month.day.year. This is the case for each of the next two doubly square dates after 4 April 2001. What are those two dates (in the same form as 4 April 2001)?

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 20 January. The Editor’s decision is final. Please send entries to Enigma 1574, ¿ìè¶ÌÊÓƵ, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1568 Odd puzzle: PUZZLE is 102235

The winner Richard Ford of Abingdon, Oxfordshire, UK