19684665

Appears in sequences

• a(n) = 5*a(n-2) - 2*a(n-4), with initial terms 0,1,1,3.at n=24A005824
• Number of labeled pure 2-complexes on n nodes (0-simplexes) with 5 2-simplexes and 9 1-simplexes.at n=18A054558
• a(n) = 5*a(n-1) - 2*a(n-2); a(0)=1, a(1)=5.at n=11A107839
• a(n) = 5*a(n-2) - 2*a(n-4), n >= 4.at n=22A109165
• a(n) = denominator(R(2*n + 1, 2*n + 1, 1)) where R(n, k, x) = Sum_{u=0..k} ( Sum_{j=0..u} x^j * binomial(u, j) * (j + 1)^n ) / (u + 1).at n=11A362999
• a(n) = denominator(R(n, n, 1)) where R(n, k, x) = Sum_{u=0..k} ( Sum_{j=0..u} x^j * binomial(u, j) * (j + 1)^n ) / (u + 1).at n=23A363001
• Expansion of (1+2*x-x^3) / (1-5*x^2+2*x^4).at n=22A384611