| Dense Packings of 3k(k+1)+1 Equal Disks in a Circle for k=1, 2, 3, 4 and 5 Recent countries visiting this post |  |
 | 4 | United States |
 | 3 | Russian Federation |
 | 1 | Germany |
| Dense Packings of 3k(k+1)+1 Equal Disks in a Circle for k=1, 2, 3, 4 and 5 Recent countries visiting this post | |
| 4 | United States |
| 3 | Russian Federation |
| 1 | Germany |