Enigma 1771: Squares either way
16 October 2013
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From New Scientist #2939, 19th October 2013 [link]
Whether you write dates in the order day.month.year or month.day.year (in each case with two digits for each element), 04.04.01 represents 4 April 2001, and it is a square date because 40401 is the square of 201.
In addition to 4 April 2001, there is one other date in this century that is written in exactly the same way in each order and is also a square date.
1) What is that date?
2) What is the next date after today that is a square date if written in the order day.month.year?
3) What is the next date after today that is a square date if written in the order month.day.year?
Give each answer in the form of 4 April 2001.