721420288

Appears in sequences

• 4th binomial transform of (1,3,0,0,0,0,0,.....).at n=13A081039
• Expansion of g.f. (1 - x)^2*(1 + x) / (1 - 2*x)^2.at n=26A106472
• a(0) = 9, a(n) = 2*a(n-1) + 2^(n-1) for n > 0.at n=25A159697