help with algorithm

[chucklarge]

Hello,
I am working on an online calculator that determines required hardware for projects.

I have a piece of hardware (DU) that supports upto 64x5 panels(that is 64 wide x 5 high) .

width and heigth are independent in the sense that you can not just multiple the panels to determine the resolution and the fit your project into the Supported specs. ie 64x5=320 so if my project is 4x10 = 40 panels, 40<320. i only need 1DU (this logic won't work).

so more correct examples

1x5 panels = 1DU
1x6 panels = 2DUs
1x11 panels = 3DUs
1x16 panels = 4DUs
1x20 panels = 4DUs

64x5 panles = 1DU
65x5 panels = 2DU
65x6 panels = 2DU
65x11 panels = 3DU

Any help with this algorithm is appreciated.

Chuck

[NogDog]

Can you explain to me why 65x6 panels = 2DU instead of 3DU, and likewise why 65x11 panels = 3DU instead of 4DU? Then maybe I'll have a better understanding of the relationships.