1143450domain: NAppears in sequencesTriangle used for the integral of odd powers of the sine and cosine functions.at n=16A254932E.g.f. A(x,k) satisfies: sin(A(x,k)) = k * sin(x).at n=18A291560Number of regular polygons that can be drawn with vertices on a centered hexagonal grid with side length n.at n=27A339483