https://mathworld.wolfram.com/CurtateCycloidEvolute.html
Curtate Cycloid Evolute -- from Wolfram MathWorld
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https://www.merriam-webster.com/dictionary/curtate
CURTATE Definition & Meaning - Merriam-Webster
The meaning of CURTATE is comparatively short or shortened; specifically, of an annuity : payable to the end of each complete year survived but not for part of...
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