A cubic number is a figurate number of the form n^3 with n a positive integer. The first few are 1, 8, 27, 64, 125, 216, 343, ... (OEIS A000578). The protagonist Christopher in the novel The Curious Incident of the Dog in the Night-Time recites the cubic numbers to calm himself and prevent himself from wanting to hit someone. The generating function giving the cubic numbers is (x(x^2 + 4x + 1))/(x - 1)^4 = x + 8x^2 + 27x^3 + .... The hex pyramidal numbers are equivalent to the cubic numbers.