Newtonian telescope secondary mirror. This design reduces the size and cost of the telescope with a shorter overall telescope tube length (with the corrector extending the focal length in a "telephoto" type layout) combined with a less costly spherical mirror. Commercially produced versions of this design have been noted to be optically compromised due to the difficulty of producing a correctly shaped sub-aperture corrector in a telescope targeted at the inexpensive end of the telescope market. Newtonian telescope The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir
Table of Newtonian series Table of Newtonian series In mathematics, a Newtonian series, named after Isaac Newton, is a sum over a sequence formula_1 written in the form where is the binomial coefficient and formula_4 is the rising factorial. Newtonian series often appear in relations of the form seen in umbral calculus. The generalized binomial theorem gives A proof for this identity can be obtained by showing that it satisfies the differential equation The digamma function: The Stirling numbers of the second kind are given by the finite sum This formula is a special case of the "k"th forward difference of the monomial "x"