# November, 2015

## Ask Uncle Colin: Is my friend crazy?

Dear Uncle Colin, A friend of mine told me that $1 + 2 + 4 + 8 + ... = -1$. Is he crazy, or is there something going on here? -- Somehow Enumerating Ridiculous Infinitely Extended Sum Dear SERIES, There are a couple of 'proofs' of this non-fact that

## Review: Sumaze

Even as someone who owes at least some of his maths skills to computer games (I played L in the late 80s and would love to see it resurrected, and there's a lot to be said for the mental arithmetic in something like Football Manager), my heart still sinks a

## Rewriting a function without going piecewise

You know the ridiculous kind of pseudo-context question that makes you go 'Why doesn't Lisa get a proper hobby rather than timing her friends doing jigsaw puzzles?'? You could replace pretty much all of them with "A mathematician is trying to be clever by...". In this particular case, a mathematician