We define a sequence of finite sums of cotangents at arguments equal to selected rational multiples of π, with the selection made by a certain order-relation algorithm. We then show how these sums are related to information about the location of the zeros of the Dirichlet L function L(s, χ4).
Links:
[1] http://www.mpim-bonn.mpg.de/de/taxonomy/term/39
[2] http://www.mpim-bonn.mpg.de/de/node/3444
[3] http://www.mpim-bonn.mpg.de/de/node/7239