New posts in Trigonometric Sums

The complex trigonometric function degenerates to the positive integer

Better trigonometrical inequalities for $\zeta(s)$?

A conjectural trigonometric identity

Something interesting about the quintic $x^5 + x^4 - 4 x^3 - 3 x^2 + 3 x + 1=0$ and its cousins