All preferences are stored on your device.
2018
It is built from checkable properties of the record itself: whether the article has a DOI, how many independent sources confirmed its data, whether the required fields are filled in, and how recent the latest confirmation is. Disagreement between sources and a missing identifier lower it. A value of 80 or above means the record was published without further checking; 60 to 79 means it is published at reduced confidence, with a manual check advisable. A record verified by an editor by hand is never pushed below 90 by a recalculation. This scores our data about the article, not the article itself.
We consider the spectral problem for operators generated by ordinary differential equations. A degenerate operator means an operator whose point spectrum fills the whole complex plane, or a resolvent set fills the whole complex plane. Conditions are found for the coefficients of the general differential equation for which the corresponding operator is degenerate.