I should have specified that they should be positive integers because Michael Hodge pointed out that n, -n, 0 would work for any integer value of n.

The answer expected was 1,2,3 which was the answer received from Michael Hodge, John Stafford, Roger Skidmore, Jane Willis, Rosemary West, Liam Thom, John Bownas and Jerry Tepper. Michael Hodge won the draw and a £5 book token. John Stafford won the prize last month and so was excluded this month. Rosemary West said not to include her in the draw and Jane Willis is not a member so there were only five persons in the draw. Well done all of you. Non members are welcome to send me answers and are invited to join the club. A membership application form is available from the documents section of the web site.