HARRY, Tom and I were challenged to find a pair of positive integers, each consisting of two different digits and one being the reverse of the other, such that neither integer was a prime or a perfect square or a multiple of any perfect square other than 1.
Harry found two such pairs; the factors of the integers in either pair were not necessarily all different but if one disregards 1 as a factor they were all different from the factors of the integers in the other pair. Tom found two other such pairs; once again the factors of the integers in either pair were not necessarily all different but if one disregards 1 as a factor they were all different from the factors of the integers in the other pair.
I found another pair of integers which Harry and Tom had not found. Which integers did I find?
A £10 book token will be awarded to the sender of the first correct answer opened on Thursday 4 May. The Editor’s decision is final. Please send entries to Enigma 816, Â鶹´«Ã½, King’s Reach Tower, Stamford Street, London SE99 0BB. The winner of Enigma 810 was Ã¥ke Nord of Sweden.
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Answer to Enigma 810
Wooded acres 2.811 feet
