24893440

Appears in sequences

• a(n) = 2^n * (2*n)! / (n!)^2.at n=9A059304
• Number of rooted unicursal planar maps with n edges and exactly one vertex of valency 1 (unicursal means that exactly two vertices are of odd valency; there is an Eulerian path).at n=9A069722
• E.g.f. BesselI(0,2*sqrt(2)*x) + BesselI(1,2*sqrt(2)*x)/sqrt(2).at n=18A098660
• Expansion of (sqrt(1-8*x^2)+8*x^2+2*x-1)/(2*x*sqrt(1-8*x^2)).at n=18A103973
• a(n) = binomial(n+9,9)*2^n.at n=9A140354
• 8-quantum transitions in systems of N >= 8 spin 1/2 particles, in columns by combination indices.at n=26A213350
• 9-quantum transitions in systems of N >= 9 spin 1/2 particles, in columns by combination indices.at n=25A213351