A generalization of Schröter's formula.
Blecksmith-Brillhart-Gerst Theorem
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References
Berndt, B. C. Ramanujan's Notebooks, Part III. New York: Springer-Verlag, p. 73, 1985.Referenced on Wolfram|Alpha
Blecksmith-Brillhart-Gerst TheoremCite this as:
Weisstein, Eric W. "Blecksmith-Brillhart-Gerst Theorem." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Blecksmith-Brillhart-GerstTheorem.html