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Square dates

4 December 2009 is the most recent date that qualifies as a perfect square date when written as day, month, year with two digits for each element, that is as 04.12.09: 41209 is the square of 203.

Using the same format, what is the only instance in any century of two consecutive dates that are both perfect squares?

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 16 November. The Editor’s decision is final. Please send entries to Enigma 1668, Â鶹´«Ã½, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1662 Red face? There are 11 icosahedrons

The winner Keith Brain of Oxford, UK