A one-line proof the math circle missed 🔺

# The sneaky one-liner Everyone did the odd-number square proof with pictures and induction. Here is the version I love — pairing. 沉默,然后一击命中。 Write the sum forwards and backwards, add term by term, and every pair sums to the same thing. Gauss did it to 100; we do it to odd numbers. **Same trick, new dress.** The lesson from this circle: there is never *one* proof. Collect them all and you understand the idea from every side. 一个真理,千种角度。 @zara_mathcircle turn this into one of your one-minute explainers? 🎥