### Fiendish dot test that conceals objects inside coloured circles leaves the web stumped

The trend for baffling brainteasers shows no sign of abating and a new puzzle now puts your eyesight to the test. You may think you're observant but a series of coloured circles concealing shapes within them are leaving the web scratching their heads. Some of the dots are easier than others and you may be forgiven for thinking there's nothing at all in others. Can you spot the object inside this bright red circle? The Playbuzz puzzle is dividing readers for that reason.

### Vicious Circle Principle and Logic Programs with Aggregates

The paper presents a knowledge representation language $\mathcal{A}log$ which extends ASP with aggregates. The goal is to have a language based on simple syntax and clear intuitive and mathematical semantics. We give some properties of $\mathcal{A}log$, an algorithm for computing its answer sets, and comparison with other approaches.

### A quick look at the Spinny Circle app

This game requires fast-tapping and quick pattern recognition to succeed. A bouncing ball in the center of Spinny Circle's multicolored wheel changes color with each hit; it's up to players to tap and turn the wheel so that the ball lands on the corresponding section of the wheel. It's not complicated, but it can be difficult, particularly since the wheel turns in only one direction. Get a mismatch on impact, and it's game over. The free version of the app will call up an ad every three failures -- which can be pretty frequent, depending on your performance.

### 'Ancient' Aberdeenshire stone circle found to be replica

An Aberdeenshire stone circle initially thought to be thousands of years old has been identified as a modern replica. An investigation into the site at the parish of Leochel-Cushnie found the stones to be about 20 years old. It was originally thought to be the site of another recumbent stone circle - until the person who built it came forward. The findings sparked excitement among experts and were widely reported. Further archaeological analysis of the stones was being conducted when a former owner of the farm contacted Mr Welfare to say they had built the stone circle in the 1990s.

### Secret monument discovered

Hidden beneath the world's largest prehistoric stone circle, archaeologists in England have discovered an even older, secret square-shaped megalithic monument. "Our research has revealed previously unknown megaliths inside the world-famous Avebury stone circle. We have detected and mapped a series of prehistoric standing stones that were subsequently hidden and buried, along with the positions of others likely destroyed during the 17th and 18th centuries," Mark Gillings, academic director and reader in archaeology in the School of Archaeology and Ancient History at the University of Leicester, said in a statement. "Together, these reveal a striking and apparently unique square megalithic monument within the Avebury circles that has the potential to be one of the very earliest structures on this remarkable site." The new finds are shocking for such an old site, which has been extensively studied by archaeologists since the 1600s.