Tag Archives: Jack van Lint

A request

In 1956, Helmut Wielandt proved that a primitive permutation group whose degree is twice a prime p is doubly transitive, unless p has the form 2a2+2a+1, in which case the group has rank 3, and its subdegrees are a(2a+1) and … Continue reading

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From M12 to M24

On 20 January 2015, Paul Hjelmstad posted the following question on the GAP forum: Is there an easy way to generate a Steiner system S(5,8,24) for the Mathieu Group M24, if a Steiner system S(5,6,12) for the Mathieu Group M12 … Continue reading

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The word “solutions” is much overused, even misused, now. When I see a van with “Cleaning solutions” on the side, I imagine it full of containers of ammonia or soapy water, while “Printing solutions” can only mean ink … But … Continue reading

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Andries Brouwer is (nearly) 60

Last week there was a conference for Andries Brouwer’s 60th birthday. Actually he is 60 on 3/4/2011, but we had some lectures to celebrate his birthday on 4/3/2011. The picture shows Andries at my birthday party in Ambleside in 2007 … Continue reading

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