183412domain: NAppears in sequencesStirling-like number triangle defined by paired decomposition of C(n+3,3) = A000292.at n=47A080416Expansion of x^2/((1-4*x)*(1-3*x)^2).at n=9A086443Triangle of 3-Eulerian numbers.at n=43A144697a(n) = 4^n - binomial(n,2)*3^(n-2).at n=9A380249