Neighbor Sum Avoidance
Can you arrange the numbers 1-9 in a circle so that the sum of two neighbors is never divisible by 3, 5, or 7?
Drag numbers from below into the circle slots.
Adjacent numbers that sum to a multiple of 3, 5, or 7 will show a red arc.
Click a filled slot to remove the number.
1
2
3
4
5
6
7
8
9