¿ìè¶ÌÊÓƵ

Consistently older

Yesterday was Harry’s birthday and also Tom’s birthday. Harry is the older. Harry’s current age, Tom’s current age and the difference between their ages are each the product of two primes. The six primes are all different.

Before Harry reaches the age of 90, there will be three further years during which his age, Tom’s age and the difference between their ages will again each be the product of two primes, the six primes all being different.

What is Harry’s current age?

WIN £15 will be awarded to the sender of the first correct answer opened on Wednesday 11 November. The Editor’s decision is final. Please send entries to Enigma 1566, ¿ìè¶ÌÊÓƵ, Lacon House, 84 Theobald’s Road, London WC1X 8NS, or to enigma@newscientist.com (please include your postal address).

Answer to 1560 Alphabetically: The numerical value of ALPHABETICALLY is 81378406928115

The winner W. Day of Orpington, Kent, UK