413342

Appears in sequences

• a(n) = Sum_{k=0..2n} (k+1) * A027082(n, 2n-k).at n=11A027107
• Numbers of the form i*9^j-1 (i=1..8, j >= 0).at n=46A140576
• a(n) = 7*9^n - 1.at n=5A198965
• Expansion of g.f.: (1 + x - 2*x^2 + 2*x^4)/((1-x)*(1-3*x^2)).at n=23A358027