190112

Appears in sequences

• G.f. is 1 - 1/f(x), where f(x) = 1+x+3*x^2+9*x^3+32*x^4+... is 1/x times g.f. for A063020.at n=10A007858
• a(n) = (2*n-3)*4^(n-1) - 2*binomial(2*n, n-1).at n=5A304202