Dandelion coffee In 1919, dandelion root was noted as a source of cheap 'coffee'. It has also been part of edible plant classes dating back at least to the 1970s. Harvesting dandelion roots requires differentiating 'true' dandelions ("Taraxacum" spp.) from other yellow daisy-like flowers such as catsear and hawksbeard. True dandelions have a ground-level rosette of deep-toothed leaves and hollow straw-like stems. Large plants that are 3–4 years old, with taproots approximately 0.5 inch (13 mm) in diameter, are harvested for dandelion coffee. These taproots are similar in appearance to pale carrots. After harvesting, the dandelion roots are dried, chopped, and roasted.
Root of unity modulo n it is not a primitive root, then there would be some divisor ℓ of "k", with formula_57. In order to exclude this possibility, one has only to check for a few ℓ's equal "k" divided by a prime. That is, what needs to be checked is: Among the primitive "k"-th roots of unity, the primitive formula_23-th roots are most frequent. It is thus recommended to try some integers for being a primitive formula_23-th root, what will succeed quickly. For a primitive formula_23-th root "x", the number formula_30 is a primitive formula_25-th root of unity. If "k" does not divide formula_23,