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WOLFRAM|DEMONSTRATIONS PROJECT

Double Helix

​
pitch
position helix 2
number in a turn
rungs
sphere diameters 1
sphere diameters 2
helix cylinder diameters
helix cylinder lengths

The structure resembles the geometry of DNA's double helix when there are 10 cylinders in a turn, the relative angular position of one helix to the other is 144 degrees, and the pitch is about 0.5.