4,10,_,82,244,730
1, 2, 3, 4, 5, 6
4,10,__,82,244,730
3^1=3
3^2=9
3^3=27
3^4=81
3^5=243
3^n+1
the missing one is 28
You beat me by a about a second Alan. LOL :)
find series
The series can be produced from 3^n + 1.
n 3^n + 1
1 4
2 10
3 28
4 82
5 244
6 730
.