-1781domain: ZAppears in sequencesExpansion of (1-x)^(-1)/(1-2*x+2*x^2+2*x^3).at n=12A077862A nonsense sequence.at n=65A152462G.f.: Sum_{n=-oo..+oo} x^(n*(n+1)/2) * C(x)^(3*n-3), where C(x) = 1 + x*C(x)^2 is the g.f. of the Catalan numbers (A000108).at n=15A355348