Image 1 of 1
Ollerenshaw-magic-square-2.jpg
Dame Kathleen Ollerenshaw, British mathematician, astronomer, politician and educationalist with one of the most-perfect magic squares, a field of mathematics in which she specialised. Dame Kathleen will be 100 years old on October 1 2012 and this photograph was taken on publictaion of her first book, on most-perfect pandiagonal magic squares, when aged 86. The missing number is 2.