2000526domain: NAppears in sequencesNumber of loopless tree-rooted planar maps with 3 vertices and n faces and no isthmuses.at n=32A006428Number of nonnegative integer solutions to n = x_1 + x_2 + ... + x_(2*n) + 2*y_1 + 2*y_2 + ... + 2*y_(2*n).at n=7A351857