161082domain: NAppears in sequences11^n+2^n-1.at n=5A155595Number of tilings of an equilateral triangle of side length n with unit triangles (of side length 1) and exactly two unit "lozenges" or "diamonds" (also of side length 1).at n=19A326367Expansion of (1/x) * Series_Reversion( x * (1 - x^3 * (1 + x)^3) ).at n=16A389407